tag:blogger.com,1999:blog-65790478527521824742024-02-20T17:40:01.708-08:00Interview PreparationAnonymoushttp://www.blogger.com/profile/04507571807515872955noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-6579047852752182474.post-58256532920280088032012-06-28T00:52:00.002-07:002012-06-28T00:52:42.973-07:00Oracle interview PART 3<div dir="ltr" style="text-align: left;" trbidi="on">
<br />
<strong>Define Transaction ?</strong><br />
A Transaction is a logical unit of work that comprises one or more <span class="klink">SQL statements</span> executed
by a single user.<br />
<br />
<br />
<strong>What is Read-Only Transaction ?</strong><br />
A Read-Only transaction ensures that the results of each query executed in the
transaction are consistant with respect to the same point in time.<br />
<br />
<br />
<strong>What is a deadlock ? Explain .</strong><br />
Two processes wating to update the rows of a table which are locked by the
other process then deadlock arises. In a <span class="klink">database environment</span> this
will often happen because of not issuing proper row lock commands. Poor design
of front-end application may cause this situation and the performance of server
will reduce drastically.<br />
These locks will be released automatically when a commit/rollback operation
performed or any one of this processes being killed externally.<br />
<br />
<br />
<strong>What is a Schema ?</strong><br />
The set of objects owned by user account is called the schema.<br />
<br />
<br />
<strong>What is a cluster Key ?</strong><br />
The related columns of the tables are called the cluster key. The cluster key
is indexed using a cluster index and its value is stored only once for multiple
tables in the cluster.<br />
<br />
<br />
<strong>What is Parallel Server ?</strong><br />
Multiple instances accessing the same database (Only In Multi-CPU environments)<br />
<br />
<br />
<strong>What are the basic element of Base configuration of an oracle Database
?</strong><br />
It consists of<br />
one or more data files.<br />
one or more control files.<br />
two or more redo log files.<br />
The Database contains<br />
multiple users/schemas<br />
one or more rollback segments<br />
one or more tablespaces<br />
<span class="klink">Data dictionary</span> tables<br />
User objects (table,indexes,views etc.,)<br />
The server that access the database consists of<br />
SGA (Database buffer, Dictionary Cache Buffers, Redo log buffers, Shared SQL
pool)<br />
SMON (System MONito)<br />
PMON (Process MONitor)<br />
LGWR (LoG Write)<br />
DBWR (Data Base Write)<br />
ARCH (ARCHiver)<br />
CKPT (Check Point)<br />
RECO<br />
Dispatcher<br />
User Process with associated PGS<br />
<br />
<br />
<strong>What is clusters ?</strong><br />
Group of tables physically stored together because they share common columns
and are often used together is called Cluster.<br />
<br />
<br />
<strong>What is an Index ? How it is implemented in Oracle Database ?</strong><br />
An index is a database structure used by the server to have direct access of a
row in a table. An index is automatically created when a unique of primary key
constraint clause is specified in create table comman (Ver 7.0)<br />
<br />
<br />
<strong>What is a <span class="klink">Database instance</span> ?
Explain</strong><br />
A database instance (Server) is a set of memory structure and background processes
that access a set of database files.<br />
The process can be shared by all users. The memory structure that are used to
store most queried data from database. This helps up to improve <span class="klink">database performance</span> by
decreasing the amount of I/O performed against data file.<br />
<br />
<br />
<strong>What is the use of ANALYZE command ?</strong><br />
To perform one of these function on an index,table, or cluster:<br />
- To collect statistics about object used by the optimizer and store them in
the data dictionary.<br />
- To delete statistics about the object used by object from the data
dictionary.<br />
- To validate the structure of the object.<br />
- To identify migrated and chained rows of the table or cluster.<br />
<br />
<br />
<strong>What is default tablespace ?</strong><br />
The Tablespace to contain schema objects created without specifying a
tablespace name.<br />
<br />
<br />
<strong>What are the system resources that can be controlled through Profile ?</strong><br />
The number of concurrent sessions the user can establish the CPU processing
time available to the user's session the CPU processing time available to a
single call to ORACLE made by a SQL statement the amount of logical I/O
available to the user's session the amout of logical I/O available to a single
call to ORACLE made by a SQL statement the allowed amount of idle time for the
user's session the allowed amount of connect time for the user's session.<br />
<br />
<br />
<strong>What is Tablespace Quota ?</strong><br />
The collective amount of disk space available to the objects in a schema on a
particular tablespace.<br />
<br />
<br />
<strong>What are the different Levels of Auditing ?</strong><br />
Statement Auditing, Privilege Auditing and Object Auditing.<br />
<br />
<br />
<strong>What is Statement Auditing ?</strong><br />
Statement auditing is the auditing of the powerful system privileges without
regard to specifically named objects.<br />
<br />
<br />
<strong>What are the <span class="klink">database administrators</span>
utilities available ?</strong><br />
SQL * DBA - This allows DBA to monitor and control an ORACLE database. SQL *
Loader - It loads data from standard operating system files (Flat files) into
ORACLE database tables. Export (EXP) and Import (imp) utilities allow you to
move existing data in ORACLE format to and from ORACLE database.<br />
<br />
<br />
<strong>How can you enable automatic archiving ?</strong><br />
Shut the database<br />
Backup the database<br />
Modify/Include LOG_ARCHIVE_START_TRUE in init.ora file.<br />
Start up the database.<br />
<br />
<br />
<strong>What are roles? How can we implement roles ?</strong><br />
Roles are the easiest way to grant and manage common privileges needed by
different groups of database users. Creating roles and assigning provides to
roles. Assign each role to group of users. This will simplify the job of
assigning privileges to individual users.<br />
<br />
<br />
<strong>What are Roles ?</strong><br />
Roles are named groups of related privileges that are granted to users or other
roles.<br />
<br />
<br />
<strong>What are the use of Roles ?</strong><br />
REDUCED GRANTING OF PRIVILEGES - Rather than explicitly granting the same set
of privileges to many users a database administrator can grant the privileges
for a group of related users granted to a role and then grant only the role to
each member of the group.<br />
DYNAMIC PRIVILEGE MANAGEMENT - When the privileges of a group must change, only
the privileges of the role need to be modified. The security domains of all
users granted the group's role automatically reflect the changes made to the
role.<br />
SELECTIVE AVAILABILITY OF PRIVILEGES - The roles granted to a user can be
selectively enable (available for use) or disabled (not available for use).
This allows specific control of a user's privileges in any given situation.<br />
APPLICATION AWARENESS - A database application can be designed to automatically
enable and disable selective roles when a user attempts to use the application.<br />
<br />
<br />
<strong>What is Privilege Auditing ?</strong><br />
Privilege auditing is the auditing of the use of powerful system privileges
without regard to specifically named objects.<br />
<br />
<br />
<strong>What is Object Auditing ?</strong><br />
Object auditing is the auditing of accesses to specific schema objects without
regard to user.<br />
<br />
<br />
<strong>What is Auditing ?</strong><br />
Monitoring of user access to aid in the investigation of database use.<br />
</div>Anonymoushttp://www.blogger.com/profile/04507571807515872955noreply@blogger.com0tag:blogger.com,1999:blog-6579047852752182474.post-64935028246704149832012-06-27T22:18:00.005-07:002012-06-27T22:18:58.728-07:00Oracle interview PART 2<div dir="ltr" style="text-align: left;" trbidi="on">
<br />
<strong>Can a view based on another view?</strong><br />
Yes.<br />
<br />
<br />
<strong>What are the advantages of views?</strong><br />
- Provide an additional level of table security, by restricting access to a
predetermined set of rows and columns of a table.<br />
- Hide data complexity.<br />
- Simplify commands for the user.<br />
- Present the data in a different perspective from that of the base table.<br />
- Store complex queries.<br />
<br />
<br />
<strong>What is an Oracle sequence?</strong><br />
A sequence generates a serial list of unique numbers for numerical columns of a
database's tables.<br />
<br />
<br />
<strong>What is a synonym?</strong><br />
A synonym is an alias for a table, view, sequence or program unit.<br />
<br />
<br />
<strong>What are the types of synonyms?</strong><br />
There are two types of synonyms private and public.<br />
<br />
<br />
<strong>What is a private synonym?</strong><br />
Only its owner can access a private synonym.<br />
<br />
<br />
<strong>What is a public synonym?</strong><br />
Any database user can access a public synonym.<br />
<br />
<br />
<strong>What are synonyms used for?</strong><br />
- Mask the real name and owner of an object.<br />
- Provide public access to an object<br />
- Provide location transparency for tables, views or program units of a remote
database.<br />
- Simplify the <span class="klink">SQL statements</span> for
database users.<br />
<br />
<br />
<strong>What is an Oracle index?</strong><br />
An index is an optional structure associated with a table to have direct access
to rows, which can be created to increase the performance of data retrieval.
Index can be created on one or more columns of a table.<br />
<br />
<br />
<strong>How are the index updates?</strong><br />
Indexes are automatically maintained and used by Oracle. Changes to table data
are automatically incorporated into all relevant indexes.<br />
<br />
<br />
<strong>What is a Tablespace?</strong><br />
A database is divided into Logical Storage Unit called tablespace. A tablespace
is used to grouped related logical structures together<br />
<br />
<br />
<strong>What is Rollback Segment ?</strong><br />
A Database contains one or more Rollback Segments to temporarily store
"undo" information.<br />
<br />
<br />
<strong>What are the Characteristics of Data Files ?</strong><br />
A data file can be associated with only one database. Once created a data file
can't change size. One or more data files form a logical unit of database
storage called a tablespace.<br />
<br />
<br />
<strong>How to define Data Block size ?</strong><br />
A data block size is specified for each ORACLE database when the database is
created. A database users and allocated free database space in ORACLE data
blocks. Block size is specified in INIT.ORA file and can’t be changed latter.<br />
<br />
<br />
<strong>What does a Control file Contain ?</strong><br />
A Control file records the physical structure of the database. It contains the
following information.<br />
<span class="klink">Database Name</span><br />
Names and locations of a database's files and redolog files.<br />
Time stamp of database creation.<br />
<br />
<br />
<strong>What is difference between UNIQUE constraint and PRIMARY KEY constraint
?</strong><br />
A column defined as UNIQUE can contain Nulls while a column defined as PRIMARY
KEY can't contain Nulls.<br />
<br />
<br />
<strong>What is Index Cluster ?</strong><br />
A Cluster with an index on the Cluster Key<br />
<br />
<br />
<strong>When does a Transaction end ?</strong><br />
When it is committed or Rollbacked.<br />
<br />
<br />
<strong>What is the effect of setting the value "ALL_ROWS" for
OPTIMIZER_GOAL parameter of the ALTER SESSION command ? What are the factors
that affect OPTIMIZER in choosing an Optimization approach ?</strong><br />
Answer The OPTIMIZER_MODE initialization parameter Statistics in the <span class="klink">Data Dictionary</span> the
OPTIMIZER_GOAL parameter of the ALTER SESSION command hints in the statement.<br />
<br />
<br />
<strong>What is the effect of setting the value "CHOOSE" for
OPTIMIZER_GOAL, parameter of the ALTER SESSION Command ?</strong><br />
The Optimizer chooses Cost_based approach and optimizes with the goal of best
throughput if statistics for atleast one of the tables accessed by the SQL
statement exist in the data dictionary. Otherwise the OPTIMIZER chooses
RULE_based approach.<br />
<br />
<br />
<strong>How does one create a new database? (for DBA)</strong><br />
One can create and modify Oracle databases using the Oracle "dbca"
(Database Configuration Assistant) utility. The dbca utility is located in the
$ORACLE_HOME/bin directory. The Oracle Universal Installer (oui) normally
starts it after installing the database server software.<br />
One can also <span class="klink">create databases</span> manually
using scripts. This option, however, is falling out of fashion, as it is quite
involved and error prone. Look at this example for creating and <span class="klink">Oracle 9i</span> database:<br />
CONNECT SYS AS SYSDBA<br />
ALTER SYSTEM SET DB_CREATE_FILE_DEST='/u01/oradata/';<br />
ALTER SYSTEM SET DB_CREATE_ONLINE_LOG_DEST_1='/u02/oradata/';<br />
ALTER SYSTEM SET DB_CREATE_ONLINE_LOG_DEST_2='/u03/oradata/';<br />
CREATE DATABASE;<br />
<br />
<br />
<strong>What database block size should I use? (for DBA)</strong><br />
Oracle recommends that your database block size match, or be multiples of your
operating system block size. One can use smaller block sizes, but the
performance cost is significant. Your choice should depend on the type of
application you are running. If you have many small transactions as with OLTP,
use a smaller block size. With fewer but larger transactions, as with a DSS
application, use a larger block size. If you are using a volume manager,
consider your "operating system block size" to be 8K. This is because
volume manager products use 8K blocks (and this is not configurable).<br />
<br />
<br />
<strong>What are the different approaches used by Optimizer in choosing an <span class="klink">execution plan</span> ?</strong><br />
Rule-based and Cost-based.<br />
<br />
<br />
<strong>What does ROLLBACK do ?</strong><br />
ROLLBACK retracts any of the changes resulting from the SQL statements in the
transaction.<br />
<br />
<br />
<strong>How does one coalesce free space ? (for DBA)</strong><br />
SMON coalesces free space (extents) into larger, contiguous extents every 2
hours and even then, only for a short period of time.<br />
SMON will not coalesce free space if a tablespace's default storage parameter
"pctincrease" is set to 0. With Oracle 7.3 one can manually coalesce
a tablespace using the ALTER TABLESPACE ... COALESCE; command, until then use:<br />
SQL> alter session set events 'immediate trace name coalesce level n';<br />
Where 'n' is the tablespace number you get from SELECT TS#, NAME FROM SYS.TS$;<br />
You can get status information about this process by selecting from the
SYS.DBA_FREE_SPACE_COALESCED dictionary view.<br />
<br />
<br />
<strong>How does one prevent tablespace fragmentation? (for DBA)</strong><br />
Always set PCTINCREASE to 0 or 100.<br />
Bizarre values for PCTINCREASE will contribute to fragmentation. For example if
you set PCTINCREASE to 1 you will see that your extents are going to have weird
and wacky sizes: 100K, 100K, 101K, 102K, etc. Such extents of bizarre size are
rarely re-used in their entirety. PCTINCREASE of 0 or 100 gives you nice round
extent sizes that can easily be reused. E.g.. 100K, 100K, 200K, 400K, etc.<br />
<br />
Use the same extent size for all the segments in a given tablespace. Locally
Managed tablespaces (available from 8i onwards) with uniform extent sizes
virtually eliminates any tablespace fragmentation. Note that the number of
extents per segment does not cause any performance issue anymore, unless they
run into thousands and thousands where additional I/O may be required to fetch
the additional blocks where extent maps of the segment are stored.<br />
<br />
<br />
<strong>Where can one find the high water mark for a table? (for DBA)</strong><br />
There is no single system table, which contains the high water mark (HWM) for a
table. A table's HWM can be calculated using the results from the following SQL
statements:<br />
SELECT BLOCKS<br />
FROM DBA_SEGMENTS<br />
WHERE OWNER=UPPER(owner) AND SEGMENT_NAME = UPPER(table);<br />
ANALYZE TABLE owner.table ESTIMATE STATISTICS;<br />
SELECT EMPTY_BLOCKS<br />
FROM DBA_TABLES<br />
WHERE OWNER=UPPER(owner) AND SEGMENT_NAME = UPPER(table);<br />
Thus, the tables' HWM = (query result 1) - (query result 2) - 1<br />
NOTE: You can also use the DBMS_SPACE package and calculate the HWM =
TOTAL_BLOCKS - UNUSED_BLOCKS - 1.<br />
<br />
<br />
<strong>What is COST-based approach to optimization ?</strong><br />
Considering available access paths and determining the most efficient execution
plan based on statistics in the data dictionary for the tables accessed by the
statement and their associated clusters and indexes.<br />
<br />
<b><br />
<strong>What does COMMIT do ?</strong></b><br />
COMMIT makes permanent the changes resulting from all SQL statements in the
transaction. The changes made by the SQL statements of a transaction become
visible to other user sessions transactions that start only after transaction
is committed.<br />
<br />
<br />
<strong>How are extents allocated to a segment? (for DBA)</strong><br />
Oracle8 and above rounds off extents to a multiple of 5 blocks when more than 5
blocks are requested. If one requests 16K or 2 blocks (assuming a 8K block
size), Oracle doesn't round it up to 5 blocks, but it allocates 2 blocks or 16K
as requested. If one asks for 8 blocks, Oracle will round it up to 10 blocks.<br />
Space allocation also depends upon the size of contiguous free space available.
If one asks for 8 blocks and Oracle finds a contiguous free space that is
exactly 8 blocks, it would give it you. If it were 9 blocks, Oracle would also
give it to you. Clearly Oracle doesn't always round extents to a multiple of 5
blocks.<br />
The exception to this rule is locally managed tablespaces. If a tablespace is
created with local extent management and the extent size is 64K, then Oracle
allocates 64K or 8 blocks assuming 8K-block size. Oracle doesn't round it up to
the multiple of 5 when a tablespace is locally managed.<br />
<br />
<br />
<strong>Can one rename a database user (schema)? (for DBA)</strong><br />
No, this is listed as Enhancement Request 158508. Workaround:<br />
Do a user-level export of user A<br />
create new user B<br />
Import system/manager fromuser=A touser=B<br />
Drop user A<br />
</div>Anonymoushttp://www.blogger.com/profile/04507571807515872955noreply@blogger.com0tag:blogger.com,1999:blog-6579047852752182474.post-75220774616133218272012-06-27T22:01:00.001-07:002012-06-27T22:01:14.396-07:00Oracle interview PART 1<div dir="ltr" style="text-align: left;" trbidi="on">
<br />
<div class="MsoNormal">
<b><span style="font-family: "Times New Roman","serif"; font-size: 12.0pt; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-IN;">What are
the components of <span style="color: red;">physical database</span> structure of Oracle database?</span></b><span style="font-family: "Times New Roman","serif"; font-size: 12.0pt; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-IN;"><br />
Oracle database is comprised of three types of files. One or more datafiles,
two are more redo log files, and one or more control files.<br />
<br />
<br />
<b>What are the components of logical database structure of Oracle database?</b><br />
There are tablespaces and database's schema objects.<br />
<br />
<br />
<b>What is a tablespace?</b><br />
A database is divided into Logical Storage Unit called tablespaces. A
tablespace is used to grouped related logical structures together.<br />
<br />
<br />
<b>What is SYSTEM tablespace and when is it created?</b><br />
Every Oracle database contains a tablespace named SYSTEM, which is
automatically created when the database is created. The SYSTEM tablespace
always contains the <span style="color: red;">data dictionary</span> tables for the <span style="color: red;">entire database</span>.<br />
<br />
<br />
<b>Explain the relationship among database, tablespace and data file ?</b><br />
Each databases logically divided into one or more tablespaces one or more data
files are explicitly created for each tablespace.<br />
<br />
<br />
<b>What is schema?</b><br />
A schema is collection of <span style="color: red;">database objects</span> of a user.<br />
<br />
<br />
<b>What are Schema Objects?</b><br />
Schema objects are the logical structures that directly refer to the database's
data. Schema objects include tables, views, sequences, synonyms, indexes, clusters,
<span style="color: red;">database triggers</span>, procedures, functions packages
and database links.<br />
<br />
<b><br />
Can objects of the same schema reside in different tablespaces?</b><br />
<br />
Yes.<br />
<br />
<br />
<b>Can a tablespace hold objects from different schemes?</b><br />
Yes.<br />
<br />
<br />
<b>What is Oracle table?</b><br />
A table is the basic unit of data storage in an Oracle database. The tables of
a database hold all of the user accessible data. Table data is stored in rows
and columns.<br />
<br />
<br />
<b>What is an Oracle view?</b><br />
A view is a virtual table. Every view has a query attached to it. (The query is
a SELECT statement that identifies the columns and rows of the table(s) the
view uses.)<br />
<br />
<br />
<b>What is Partial Backup ?</b><br />
A Partial Backup is any operating system backup short of a full backup, taken
while the database is open or shut down.<br />
<br />
<br />
<b>What is Mirrored on-line Redo Log ?</b><br />
A mirrored on-line redo log consists of copies of on-line redo log files
physically located on separate disks, changes made to one member of the group
are made to all members<br />
<br />
<br />
<b>What is Full Backup ?</b><br />
A full backup is an operating system backup of all data files, on-line redo log
files and control file that constitute ORACLE database and the parameter.<br />
<br />
<br />
<b>Can a View based on another View ?</b><br />
Yes.<br />
<br />
<br />
<b>Can a Tablespace hold objects from different Schemes ?</b><br />
Yes.<br />
<br />
<br />
<b>Can objects of the same Schema reside in different tablespace ?</b><br />
Yes.<br />
<br />
<br />
<b>What is the use of Control File ?</b><br />
When an instance of an ORACLE database is started, its control file is used to
identify the database and redo log files that must be opened for database
operation to proceed. It is also used in database recovery.<br />
<br />
<br />
<b>Do View contain Data ?</b><br />
Views do not contain or store data.<br />
<br />
<br />
<b>What are the Referential actions supported by FOREIGN KEY integrity
constraint ?</b><br />
<u>UPDATE and DELETE Restrict</u> - A referential <span style="color: red;">integrity rule</span> that disallows the update or
deletion of referenced data. <o:p></o:p></span></div>
<div class="MsoNormal">
<u><span style="font-family: "Times New Roman","serif"; font-size: 12.0pt; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-IN;">DELETE
Cascade</span></u><span style="font-family: "Times New Roman","serif"; font-size: 12.0pt; mso-fareast-font-family: "Times New Roman"; mso-fareast-language: EN-IN;"> - When a
referenced row is deleted all associated dependent rows are deleted.<br />
<br />
<br />
<b>What are the type of Synonyms?</b><br />
There are two types of Synonyms Private and Public.<br />
<br />
<br />
<b>What is a Redo Log ?</b><br />
The set of Redo Log files YSDATE,UID,USER or USERENV SQL functions, or the
pseudo columns LEVEL or ROWNUM.<br />
<br />
<br />
<b>What is an Index Segment ?</b><br />
Each Index has an Index segment that stores all of its data.<br />
<br />
<br />
<b>Explain the relationship among Database, Tablespace and Data file?</b><br />
Each databases logically divided into one or more tablespaces one or more data
files are explicitly created for each tablespace<br />
<br />
<br />
<b>What are the different type of Segments ?</b><br />
Data Segment, Index Segment, Rollback Segment and Temporary Segment.<br />
<br />
<br />
<b>What are Clusters ?</b><br />
Clusters are groups of one or more tables physically stores together to share
common columns and are often used together.<br />
<br />
<br />
<b>What is an Integrity Constrains ?</b><br />
An integrity constraint is a declarative way to define a business rule for a
column of a table.<br />
<br />
<br />
<b>What is an Index ?</b><br />
An Index is an optional structure associated with a table to have direct access
to rows, which can be created to increase the performance of data retrieval.
Index can be created on one or more columns of a table.<br />
<br />
<br />
<b>What is an Extent ?</b><br />
An Extent is a specific number of contiguous data blocks, obtained in a single
allocation, and used to store a specific type of information.<br />
<br />
<br />
<b>What is a View ?</b><br />
A view is a virtual table. Every view has a Query attached to it. (The Query is
a SELECT statement that identifies the columns and rows of the table(s) the
view uses.)<br />
<br />
<br />
<b>What is Table ?</b><br />
A table is the basic unit of data storage in an ORACLE database. The tables of
a database hold all of the user accessible data. Table data is stored in rows
and columns.<o:p></o:p></span></div>
</div>Anonymoushttp://www.blogger.com/profile/04507571807515872955noreply@blogger.com0tag:blogger.com,1999:blog-6579047852752182474.post-38849531195185027902012-06-27T08:46:00.000-07:002012-06-27T08:46:36.558-07:00Oracle interview questions<div dir="ltr" style="text-align: left;" trbidi="on">
<br />
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain the
difference between trigger and stored procedure.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">Trigger in act which is performed automatically before or after a
event occur<o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">Stored procedure</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">is a set of functionality which is executed when it is explicitly
invoked. </span></span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain Row
level and statement level trigger.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Row-level: - They get fired once for each row in a
table affected by the statements. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Statement: - They get fired once for each triggering
statement. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Advantage of
a stored procedure over a database trigger<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">Firing of a stored procedure can be controlled whereas on the
other hand trigger will get fired whenever any modification takes place on the
table. </span><span lang="EN-US"><o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are
cascading triggers?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A Trigger that contains statements which cause invoking of other
Triggers are known as cascading triggers. Here’s the order of execution of
statements in case of cascading triggers:<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpFirst" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Execute all </span><span lang="EN-US">BEFORE</span><span lang="EN-US"> </span><i><span lang="EN-US">statement</span></i><span lang="EN-US">
triggers that apply to the current statement. <o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<a href="" name="3560"></a><!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Loop for each row affected statement. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<a href="" name="3561"></a><!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Execute all </span><span lang="EN-US">BEFORE</span><span lang="EN-US"> </span><i><span lang="EN-US">row</span></i><span lang="EN-US"> triggers that
apply to the current statement in the loop.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<a href="" name="3562"></a><!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Lock and change row, perform integrity
constraints check; release lock.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<a href="" name="3564"></a><!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Execute all </span><span lang="EN-US">AFTER</span><span lang="EN-US"> </span><i><span lang="EN-US">row</span></i><span lang="EN-US"> triggers that
apply to the current statement.<o:p></o:p></span></div>
<div class="MsoListParagraph" style="margin: 0cm 0cm 0.0001pt 18pt; text-indent: -18pt;">
<a href="" name="3566"></a><!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Execute all </span><span lang="EN-US">AFTER</span><span lang="EN-US"> </span><i><span lang="EN-US">statement</span></i><span lang="EN-US">
triggers that apply to the current statement.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a JOIN?
Explain types of JOIN in oracle.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A JOIN is used to match/equate different fields from 2 or more
tables using primary/foreign keys. Output is based on type of Join and what is
to be queries i.e. common data between 2 tables, unique data, total data, or
mutually exclusive data.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Types of JOINS: <o:p></o:p></span></b></div>
<table border="1" cellpadding="0" cellspacing="0" class="MsoNormalTable" style="border-collapse: collapse; border: none; mso-border-alt: solid black .5pt; mso-border-insideh: .5pt solid black; mso-border-insidev: .5pt solid black; mso-padding-alt: 0cm 5.4pt 0cm 5.4pt; mso-yfti-tbllook: 1184;">
<tbody>
<tr>
<td style="border: solid black 1.0pt; mso-border-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 145.7pt;" valign="top" width="194">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">JOIN Type<o:p></o:p></span></b></div>
</td>
<td style="border-left: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 151.8pt;" valign="top" width="202">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Example<o:p></o:p></span></b></div>
</td>
<td style="border-left: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 90.65pt;" valign="top" width="121">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Description<o:p></o:p></span></b></div>
</td>
</tr>
<tr>
<td style="border-top: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 145.7pt;" valign="top" width="194">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Simple JOIN<o:p></o:p></span></b></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 151.8pt;" valign="top" width="202">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SELECT p.last_name, t.deptName<br />
FROM person p, dept t<br />
WHERE p.id <b>=</b> t.id;<o:p></o:p></span></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 90.65pt;" valign="top" width="121">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Find name and department name of
students who have been allotted a department <o:p></o:p></span></div>
</td>
</tr>
<tr>
<td style="border-top: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 145.7pt;" valign="top" width="194">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Inner/Equi/Natural JOIN<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 151.8pt;" valign="top" width="202">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SELECT * from Emp INNER JOIN
Dept WHERE Emp.empid=Dept.empid</span><b><span lang="EN-US"><o:p></o:p></span></b></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 90.65pt;" valign="top" width="121">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Extracts data that meets the
JOIN conditions only. A JOIN is by default INNER unless OUTER keyword is
specified for an OUTER JOIN.<o:p></o:p></span></div>
</td>
</tr>
<tr>
<td style="border-top: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 145.7pt;" valign="top" width="194">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Outer Join<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 151.8pt;" valign="top" width="202">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SELECT distinct * from Emp LEFT
OUTER JOIN Dept Where Emp.empid=Dept.empid</span><b><span lang="EN-US"><o:p></o:p></span></b></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 90.65pt;" valign="top" width="121">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">It includes non matching rows
also unlike Inner Join.<o:p></o:p></span></div>
</td>
</tr>
<tr>
<td style="border-top: none; border: solid black 1.0pt; mso-border-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 145.7pt;" valign="top" width="194">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Self JOIN<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 151.8pt;" valign="top" width="202">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SELECT a.name,b.name from emp a,
emp b WHERE a.id=b.rollNumber</span><b><span lang="EN-US"><o:p></o:p></span></b></div>
</td>
<td style="border-bottom: solid black 1.0pt; border-left: none; border-right: solid black 1.0pt; border-top: none; mso-border-alt: solid black .5pt; mso-border-left-alt: solid black .5pt; mso-border-top-alt: solid black .5pt; padding: 0cm 5.4pt 0cm 5.4pt; width: 90.65pt;" valign="top" width="121">
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Joining a Table to itself.<o:p></o:p></span></div>
</td>
</tr>
</tbody></table>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is object
data type in oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">New/User defined objects can be created from any database built in
types or by their combinations. It makes it easier to work with complex data
like images, media (audio/video). An object types is just an abstraction of the
real world entities. An object has:<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpFirst" style="margin-bottom: 0.0001pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Name<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpMiddle" style="margin-bottom: 0.0001pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Attributes<o:p></o:p></span></div>
<div class="MsoListParagraphCxSpLast" style="margin-bottom: 0.0001pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Methods<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Example:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Create type MyName as object
(first varchar2(20), second varchar2(20));</span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Now you can use this datatype while defining a table below:</span><span lang="EN-US"> <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Create table Emp (empno
number(5),Name MyName);</span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">One can access the Atributes as Emp.Name.First and Emp.Name.Second<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is composite
data type?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Composite data types are also known as Collections .i.e RECORD,
TABLE, NESTED TABLE, VARRAY.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Composite data types are of 2 types:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">PL/SQL RECORDS<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">PL/SQL Collections- Table, Varray, Nested Table<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Differences
between CHAR and NCHAR in Oracle<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">NCHAR allow storing of Unicode data in the database. One can store
Unicode characters regardless of the setting of the database characterset<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Differences
between CHAR and VARCHAR2 in Oracle<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">CHAR is used to store fixed length character strings where as
Varchar2 can store variable length character strings. However, for performance
sake Char is quit faster than Varchar2. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">If we have char name[10] and store “abcde”, then 5 bytes will be
filled with null values, whereas in case of varchar2 name[10] 5 bytes will be
used and other 5 bytes will be freed. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Differences
between DATE and TIMESTAMP in Oracle<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Date is used to store date and time values including month, day,
year, century, hours, minutes and seconds. It fails to provide granularity and
order of execution when finding difference between 2 instances (events) having
a difference of less than a second between them.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">TimeStamp datatype stores everything that Date stores and
additionally stores fractional seconds.<o:p></o:p></span></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">Date: </span><st1:time hour="16" minute="5" w:st="on"><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">16:05:14</span></st1:time><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;"><o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">Timestamp:</span><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;"> <st1:time hour="16" minute="5" w:st="on">16:05:14</st1:time><b>:000</b><o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Define CLOB
and NCLOB datatypes.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">CLOB</span></b><span lang="EN-US">: Character large object. It is 4GB in length.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">NCLOB</span></b><span lang="EN-US">: National Character large object. It is CLOB
datatype for multiple character sets , upto 4GB in length.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is the
BFILE datatypes?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">It refers to an external binary file and its size is
limited by the operating system.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
Varrays?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Varrays are one-dimensional, arrays. The maximum length is
defined in the declaration itself. These can be only used when you know in
advance about the maximum number of items to be stored.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">For example: One person can have multiple phone numbers. If we
are storing this data in the tables, then we can store multiple phone numbers
corresponding to single Name. If we know the maximum number of phone numbers,
then we can use Varrays, else we use nested tables.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a
cursor? What are its types?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Cursor is used to access the access the result set
present in the memory. This result set contains the records returned on
execution of a query. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">They are of 2 types: <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">1.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Explicit<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">2.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Implicit<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain the
attributes of implicit cursor<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<ol start="1" style="margin-top: 0cm;" type="a">
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%FOUND - True, if the SQL statement has changed any rows.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%NOTFOUND - True, if record was not fetched successfully.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%ROWCOUNT - The number of rows affected by the SQL statement.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%ISOPEN - True, if there is a SQL statement being associated to the
cursor or the cursor is open.<o:p></o:p></span></li>
</ol>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain the
attributes of explicit cursor.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<ol start="1" style="margin-top: 0cm;" type="a">
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%FOUND - True, if the SQL statement has changed any rows.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%NOTFOUND - True, if record was not fetched successfully.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%ROWCOUNT - The number of rows affected by the SQL statement.<o:p></o:p></span></li>
<li class="MsoNormal" style="margin-bottom: 0.0001pt;"><span lang="EN-US">%ISOPEN - True, if there is a SQL statement being associated to the
cursor or the cursor is open.<o:p></o:p></span></li>
</ol>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is the ref
cursor in Oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">REF_CURSOR allows returning a recordset/cursor from a Stored
procedure.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">It is of 2 types:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Strong REF_CURSOR</span></b><span lang="EN-US">:
Returning columns with datatype and length need to be known at compile time.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Weak REF_CURSOR</span></b><span lang="EN-US">:
Structured does not need to be known at compile time.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Syntax till
Oracle 9i<o:p></o:p></span></b></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">create or replace package REFCURSOR_PKG as<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">TYPE WEAK8i_REF_CURSOR IS REF CURSOR;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">TYPE STRONG REF_CURSOR IS REF CURSOR RETURN EMP%ROWTYPE;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">end REFCURSOR_PKG;<o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Procedure returning the REF_CURSOR:<o:p></o:p></span></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">create or replace procedure test( p_deptno IN number , p_cursor OUT <o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">REFCURSOR_PKG.WEAK8i_REF_CURSOR)<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">is<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">begin<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">open p_cursor FOR <o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">select *<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">from emp<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">where deptno = p_deptno;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">end test;<o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Since Oracle 9i
we can use SYS_REFCURSOR<o:p></o:p></span></b></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">create or replace procedure test( p_deptno IN number,p_cursor OUT SYS_REFCURSOR)<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">is<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">begin<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">open p_cursor FOR <o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">select *<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">from emp<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">where deptno = p_deptno;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">end test;<o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">For Strong<o:p></o:p></span></b></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">create or replace procedure test( p_deptno IN number,p_cursor OUT REFCURSOR_PKG.STRONG <o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">REF_CURSOR)<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">is<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">begin<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">open p_cursor FOR <o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">select *<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">from emp<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">where deptno = p_deptno;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">end test;<o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are the
drawbacks of a cursor?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Cursors allow row by row processing of recordset. For every row, a
network roundtrip is made unlike in a Select query where there is just one
network roundtrip. Cursors need more I/O and temp storage resources, thus it is
slower.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a cursor
variable?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">In case of a cursor, Oracle opens an anonymous work area that
stores processing information. This area can be accessed by cursor variable
which points to this area. One must define a REF CURSOR type, and then declare
cursor variables of that type to do so.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">E.g.:<o:p></o:p></span></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">/* Create the cursor type. */<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">TYPE company_curtype IS REF CURSOR RETURN company%ROWTYPE;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;"> </span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">/* Declare a cursor variable of that type. */<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">company_curvar company_curtype;<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;"> </span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is implicit
cursor in Oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">PL/SQL creates an implicit cursor whenever an SQL statement is
executed through the code, unless the code employs an explicit cursor. The
developer does not explicitly declare the cursor, thus, known as implicit
cursor.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">E.g.:<o:p></o:p></span></div>
<div class="para" style="margin-bottom: .0001pt; margin: 0cm;">
<span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">In the following UPDATE statement, which gives
everyone in the company a 20% raise, PL/SQL creates an implicit cursor to
identify the set of rows in the table which would be affected.<o:p></o:p></span></div>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">UPDATE emp<o:p></o:p></span></pre>
<pre><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">SET salary = salary * 1.2;<o:p></o:p></span></pre>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Can you pass a
parameter to a cursor? Explain with an explain<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Parameterized cursor:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">/*Create a table*/<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><b><span lang="EN-US" style="font-size: 10pt;">create </span></b></code><code><span lang="EN-US" style="font-size: 10pt;">table Employee(</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">ID VARCHAR2(4 BYTE)NOT NULL,</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">First_Name VARCHAR2(10 BYTE)<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">);<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">/*Insert some data*/<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><b><span lang="EN-US" style="font-size: 10pt;">Insert </span></b></code><code><span lang="EN-US" style="font-size: 10pt;">into
Employee (ID, First_Name) values (‘01’,’Harry’);<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">/*create cursor*/<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">declare</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">cursor c_emp(cin_No NUMBER)is <b>select </b>count(*) <b>from
</b>employee <b>where </b>id=cin_No;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">v_deptNo employee.id%type:=10;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">v_countEmp NUMBER;</span></code><span lang="EN-US"><br />
</span><code><b><span lang="EN-US" style="font-size: 10pt;">begin</span></b></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">open c_emp (v_deptNo);</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">fetch c_emp into v_countEmp;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;">close c_emp;</span></code><span lang="EN-US"><br />
</span><code><b><span lang="EN-US" style="font-size: 10pt;">end</span></b></code><code><span lang="EN-US" style="font-size: 10pt;">;<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">/*Using cursor*/<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Open c_emp (10);</span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a package
cursor?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A Package that returns a Cursor type is a package cursor.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Eg:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><b><span lang="EN-US" style="font-size: 10pt;">Create </span></b></code><code><span lang="EN-US" style="font-size: 10pt;">or replace
<b>package </b>pkg_Util is</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> cursor c_emp is <b>select </b>*
<b>from </b>employee;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> r_emp c_emp%ROWTYPE;</span></code><span lang="EN-US"><br />
</span><code><b><span lang="EN-US" style="font-size: 10pt;">end</span></b></code><code><span lang="EN-US" style="font-size: 10pt;">;<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><span lang="EN-US" style="font-size: 10pt;">/*Another package using this package*/<o:p></o:p></span></code></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<code><b><span lang="EN-US" style="font-size: 10pt;">Create </span></b></code><code><span lang="EN-US" style="font-size: 10pt;">or replace
<b>package body </b>pkg_aDifferentUtil is</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> <b>procedure </b>p_printEmps is</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> <b>begin</b></span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> open
pkg_Util.c_emp;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> loop</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> fetch
pkg_Util.c_emp into pkg_Util.r_emp;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> exit
when pkg_Util.c_emp%NOTFOUND;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> DBMS_OUTPUT.put_line(pkg_Util.r_emp.first_Name);</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> <b>end </b>loop;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> close
pkg_Util.c_emp;</span></code><span lang="EN-US"><br />
</span><code><span lang="EN-US" style="font-size: 10pt;"> <b>end</b>;</span></code><span lang="EN-US"><br />
</span><code><b><span lang="EN-US" style="font-size: 10pt;">end</span></b></code><code><span lang="EN-US" style="font-size: 10pt;">;</span></code><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain why
cursor variables are easier to use than cursors.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Cursor variables are preferred over a cursor for following
reasons:<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A
cursor variable is not tied to a specific query.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">One
can open a cursor variable for any query returning the right set of columns.
Thus, more flexible than cursors.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A
cursor variable can be passed as a parameter.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A
cursor variable can refer to different work areas.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
locking, advantages of locking and types of locking in oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Locking is a mechanism to ensure data integrity
while allowing maximum concurrent access to data. It is used to implement
concurrency control when multiple users access table to manipulate its data at
the same time.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Advantages of locking: <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">a.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Avoids
deadlock conditions<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">b.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Avoids
clashes in capturing the resources<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Types of locks: <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">a.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Read
Operations: Select<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">b.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Write
Operations: Insert, Update and Delete<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are
transaction isolation levels supported by Oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Oracle supports 3 transaction isolation levels: <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">a.<span style="font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Read
committed (default)<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">b.<span style="font-size: 7pt;"> </span></span><!--[endif]--><span lang="EN-US">Serializable transactions</span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">c.<span style="font-size: 7pt;"> </span></span><!--[endif]--><span lang="EN-US">Read only</span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
SQL*Loader?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SQL*Loader is a loader utility used for moving data from
external files into the <a href="http://www.orafaq.com/wiki/Oracle_database" title="Oracle database"><span style="color: black; text-decoration: none; text-underline: none;">Oracle database</span></a>
in bulk. It is used for high performance data loads.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
Program Global Area (PGA)?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US" style="color: #4d4d4d; mso-bidi-font-family: Arial;">The Program Global Area (PGA): stores data and control
information for a server process in the memory. The PGA consists of a private
SQL area and the session memory.</span></span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a
shared pool?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">The shared pool is a key component. The shared pool
is like a buffer for SQL statements. It is to store the SQL statements so
that the identical SQL statements do not have to be parsed each time they're
executed. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">38. What is
snapshot in oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">A snapshot is a recent copy of a table from db or in
some cases, a subset of rows/cols of a table. They are used to dynamically
replicate the data between distributed databases. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a
synonym?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">A</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">synonym</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">is an alternative name tables,
views, sequences and other database objects.<o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a
schema?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">A schema is a collection of database objects. Schema objects are
logical structures created by users to contain data. Schema objects include
structures like tables, views, and indexes.</span></span><span class="apple-converted-space"><span lang="EN-US"> <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are
Schema Objects?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">Schema object</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">is a logical data storage
structure. Oracle stores a schema object logically within a</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">tablespace</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">of the database. <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is a
sequence in oracle?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Is a column in a table that allows a faster
retrieval of data from the table because this column contains data which
uniquely identifies a row. It is the fastest way to fetch data through a select
query. This column has constraints to achieve this ability. The constraints are
put on this column so that the value corresponding to this column for any row
cannot be left blank and also that the value is unique and not duplicated with
any other value in that column for any row. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Difference
between a hot backup and a cold backup<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">Cold</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">backup</span></span><span class="apple-converted-space"><span lang="EN-US">: </span></span><span class="apple-style-span"><span lang="EN-US">It is taken when the database is closed and not available to
users. </span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="ilad"><span lang="EN-US">All
files</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">of the database are copied (image copy). The datafiles
cannot be changed during the backup as they are locked, so the database remains
in sync upon restore.</span></span><span class="apple-converted-space"><span lang="EN-US"> <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US"><br />
<span class="apple-style-span">Hot backup: While taking the backup, if the
database remains open and available to users then this kind of back up is
referred to as hot backup.</span><span class="apple-converted-space"> </span><span class="apple-style-span"> Image copy is made for all the files. As, the
database is in use the entire time, so there might be changes made when backup
is taking place. These changes are available in</span><span class="ilad"> log
files so the database can be kept in sync<o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are the
purposes of Import and Export utilities?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Export and Import are the utilities provided by oracle
in order to write data in a binary format from the db to OS files and to read
them back. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">These
utilities are used:<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">To take
backup/dump of data in OS files.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">Restore the
data from the binary files back to the database.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US">move data
from one owner to another<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Difference
between ARCHIVELOG mode and NOARCHIVELOG mode<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Archivelog mode is a mode in which backup is taken
for all the transactions that takes place so as to recover the database at any
point of time. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Noarichvelog
mode is in which the log files are not written. This mode has a
disadvantage that the database cannot be recovered when required. It has an
advantage over archivelog mode which is increase in performance. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US"> </span><b style="background-color: white;"><span lang="EN-US"> </span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are the
original Export and Import Utilities?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">SQL*Loader, External Tables<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are data
pump Export and Import Modes?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">It is used for fast and bulk data movement within
oracle databases. Data Pump utility is faster than the original import &
export utilities. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What are
SQLCODE and SQLERRM and why are they important for PL/SQL developers?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">SQLCODE</span></b><span lang="EN-US">: It returns the error number for the last
encountered error. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">SQLERRM</span></b><span lang="EN-US">: It returns the actual error message of the
last encountered error. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain user
defined exceptions in oracle.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">A User-defined</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">exception</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">has to be defined by
the programmer. User-defined exceptions are declared in the declaration section
with their type as</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span class="apple-style-span"><span lang="EN-US">exception. They
must be raised explicitly using RAISE statement, unlike pre-defined exceptions
that are raised implicitly. RAISE statement can also be used to raise internal
exceptions.</span></span><span class="apple-converted-space"><span lang="EN-US"> <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<strong><span lang="EN-US" style="font-family: Calibri, sans-serif;">Exception:</span></strong><span class="apple-converted-space"><span lang="EN-US"> </span></span><span lang="EN-US"><br />
<br />
</span><span class="apple-style-span"><span lang="EN-US">DECLARE <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">userdefined EXCEPTION; <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">BEGIN <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US"><Condition on which exception is to
be raised><o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">RAISE userdefined; <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">EXCEPTION <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US">WHEN userdefined THEN <o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US"><task to perform when exception is
raised><o:p></o:p></span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span class="apple-style-span"><span lang="EN-US"> END;</span></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">Explain the concepts
of Exception in Oracle. Explain its type.<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">Exception is the raised when an error occurs while
program execution. As soon as the error occurs, the program execution stops and
the control are then transferred to exception-handling part. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">There are two types of exceptions: <o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">1.<span style="font-size: 7pt;">
</span></span><!--[endif]--><b><span lang="EN-US">Predefined</span></b><span lang="EN-US"> : These types of exceptions are raised whenever something occurs
beyond oracle rules. E.g. Zero_Divide<o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt; text-indent: -18pt;">
<!--[if !supportLists]--><span lang="EN-US">2.<span style="font-size: 7pt;">
</span></span><!--[endif]--><b><span lang="EN-US">User defined</span></b><span lang="EN-US">: The ones that occur based on the condition specified by the
user. </span><span class="apple-style-span"><span lang="EN-US">They
must be raised explicitly using RAISE statement, unlike pre-defined exceptions
that are raised implicitly.</span></span><span class="apple-converted-space"><span lang="EN-US"> </span></span><span lang="EN-US"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin: 0cm 0cm 0.0001pt 36pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">How
exceptions are raised in oracle?<o:p></o:p></span></b></div>
<div class="para" style="margin-bottom: .0001pt; margin: 0cm;">
<br /></div>
<div class="para" style="margin-bottom: .0001pt; margin: 0cm;">
<span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">There are four ways that you or the PL/SQL runtime
engine can raise an exception:<o:p></o:p></span></div>
<div class="para" style="margin-bottom: .0001pt; margin-bottom: 0cm; margin-left: 36.0pt; margin-right: 0cm; margin-top: 0cm; mso-list: l9 level1 lfo4; text-indent: -18.0pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol; font-size: 11pt;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US" style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; mso-bidi-font-family: "Courier New"; mso-bidi-font-style: italic;">E</span><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;">xceptions are raised automatically by the program. <o:p></o:p></span></div>
<div class="para" style="margin-bottom: .0001pt; margin-bottom: 0cm; margin-left: 36.0pt; margin-right: 0cm; margin-top: 0cm; mso-list: l9 level1 lfo4; text-indent: -18.0pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol; font-size: 11pt;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US" style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; mso-bidi-font-family: "Courier New"; mso-bidi-font-style: italic;">The programmer raises a user defined exceptions.</span><span lang="EN-US" style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; mso-bidi-font-family: "Courier New";"> <o:p></o:p></span></div>
<div class="para" style="margin-bottom: .0001pt; margin-bottom: 0cm; margin-left: 36.0pt; margin-right: 0cm; margin-top: 0cm; mso-list: l9 level1 lfo4; text-indent: -18.0pt;">
<!--[if !supportLists]--><span lang="EN-US" style="font-family: Symbol; font-size: 11pt;">·<span style="font-family: 'Times New Roman'; font-size: 7pt;">
</span></span><!--[endif]--><span lang="EN-US" style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; mso-bidi-font-family: "Courier New"; mso-bidi-font-style: italic;"> The
programmer raises pre defined exceptions explicitly.</span><span lang="EN-US" style="font-family: Calibri, sans-serif; font-size: 11pt;"><o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
tkprof and how is it used?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">tkprof is used for diagnosing performance
issues. It formats a trace file into a more readable format for
performance analysis. It is needed because trace file is a very complicated
file to be read as it contains minute details of program execution.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<b><span lang="EN-US">What is
Oracle Server Autotrace?<o:p></o:p></span></b></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<span lang="EN-US">It is a utility that provides instant feedback on
successful execution of any statement (select, update, insert, delete). It is the most basic utility to test the
performance issues. <o:p></o:p></span></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
<div class="MsoNormal" style="margin-bottom: 0.0001pt;">
<br /></div>
</div>Anonymoushttp://www.blogger.com/profile/04507571807515872955noreply@blogger.com0