anjum

• May 1st, 2015

When update statement fires data will be loaded into buffer from data files and keeps the old image into undo tablespace and modifies the data in buffer once you commit modified data will be written to data files if you rollback data from undotablespace it will read and writes to the data files.

premk

 Profile Answers by premk Questions by premk

• Dec 23rd, 2009

When a user issues a update statement the server process checks for weather the same type of command is executed recently or not if that command is executed very recently then it directly proceed to t...

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I developed like below.Any experts query ....please send.selecttable_name,constraint_namefrom user_cons_columns where column_name=(select a.COLUMN_NAME from user_cons_columns a,user_constraints bwhere a.TABLE_NAME=b.TABLE_NAME and b.constraint_type in ('P')and a.TABLE_NAME='DEPT')and constraint_name like '%FK%'

asheesh

• Jun 2nd, 2012

select table_name from USER_CONSTRAINTS where r_constraint_name= (select CONSTRAINT_NAME from USER_CONSTRAINTS where table_name=INPUT_PARENT_TABLE and CONSTRAINT_TYPE=P) and CONSTRAINT_TYPE=R;

sen_sam86

 Profile Answers by sen_sam86 Questions by sen_sam86

• Aug 18th, 2009

Try this script, Example SELECT child.table_name AS "TABL_NAME_2", 'Is Parent Of' AS ...

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What is the difference between IS and AS in Oracle PL/SQL..?

kishanjha

 Profile Answers by kishanjha Questions by kishanjha

• Feb 28th, 2017

IS is for defining and AS is for ALIAS only

Nupur

• Apr 24th, 2015

In plsql there is no difference.

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vizaik

 Profile Answers by vizaik Questions by vizaik

• Aug 14th, 2007

In layman terms,SQL is a language to query a database.SQL plus is an editor (provided with oracle) to write/execute sql commands.

satyam_Ora

 Profile Answers by satyam_Ora Questions by satyam_Ora

• Jul 10th, 2007

Sql is the command line prompt, where we can enter commands of DDL,DML and DCL to perform transaction in database. i.esql> select * from dual;sql> select count(*) from dual;SQL*Plus is the comma...

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Transaction is unit of work done. So a database management system will have number of transactions. There may be situations when two or more transactions are put into wait state simultaneously .In this position each would be waiting for the other transaction to get released. Suppose we have two transactions one and two both executing simultaneously. In transaction numbered one we update student table...

Chittaranjan Kotian

• May 16th, 2012

Two Oracle Sessions attempting to obtain a lock on a rows that is being locked by each other. For example Session A has locked a row for update in a transaction. Session B is trying to obtain a lock o...

rohit

• Apr 22nd, 2012

It is absolutely wrong.you can read data simultaneously but you cant write data ......you can write data one at a time only...

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Waseem Mehmood

 Profile Answers by Waseem Mehmood Questions by Waseem Mehmood

• Jun 2nd, 2011

Select ename, count(ename) Count From emp Group by ename Having count(ename) > 1 ;

Showstopper

 Profile Answers by Showstopper Questions by Showstopper

• Jun 21st, 2010

We can count the duplicate entry in particular table by using the following queryselect count(*)from a bwhere exists (select rowid           &nbs...

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murali

• Nov 8th, 2011

Snapshot is just like a image of the previous data for our reference and it's useful for analysing purpose in ADDM

jeyam

• Nov 2nd, 2011

Snapshot is just like a image of the previous data for our reference and it's useful for analysing purpose in ADDM

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Which is the subset of SQL commands used to manipulate Oracle database structures, including tables?

test

• Jan 5th, 2016

DDL is used to define database structure (cerate , alter, drop, truncate)
DML is used to manipulate data ( select, insert, update, delete)
So DDL is used to manipulate database

sri ram reddy

• Nov 14th, 2015

Alter command manipulates Oracle database structures including tables

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How to check errors from plsql package not by log file not by "show err"from sql * plus provided concurrent program name

prakash

• Jun 8th, 2015

Using dbms_utility.format_error_mask function will be used to get errors from that package.

Karthik Sai

• Feb 2nd, 2015

Using exception / dbms output are the best and easier methods

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Ashish

• Mar 24th, 2012

See, in oracle to maintain read consistency oracle keeps a copy in undo section of database for the data which is under modification by some transaction. And so readers do not wait for writers and ca...

Kranthi

• Jul 13th, 2011

In before update/delete trigger if we use select statement for fetching the records.in this scenario will wet mutating trigger error.using row level trigger we can avoid instead of statement level trigger. we can accurate results.

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Ajit bartakke

• Aug 24th, 2016

Pro*C is a Pre-compiler tool and OCI is a intermidator

Adas

• Nov 1st, 2012

Can anyone tell the exact diff b/w Pro*C and OCI

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tej

• Apr 23rd, 2012

The Oracle version starting of I. The starting in 1999 with version 6i, 8i and 9i, I signify "Internet" means stands for "Internet" and Oracle added the "I" to the version name to reflect support for ...

pradeep

• Aug 2nd, 2011

Oracle 9i and Oracle 10g....there are more implementation differences. In terms of architecture, 9i is based on Internet technology while 10g is grid computing based one. Many DBA features like Automa...

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PK

• Feb 29th, 2012

There is one Oracle function ROLLUP, the same can be used for required output

QUERY:
SELECT GENDER,COUNT(GENDER)
FROM TABLE_NAME GROUP BY ROLLUP(GENDER);

neelapu

 Profile Answers by neelapu Questions by neelapu

• Apr 16th, 2010

SELECT COUNT(decode(sex1,'F',1)) "female count", COUNT(decode(sex1,'m',1)) "male count", COUNT(*) "total count"  FROM

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RenukaRajput

 Profile Answers by RenukaRajput Questions by RenukaRajput

• Nov 29th, 2007

delete table_name where col_name in(select col_name from table_name group by col_name having count(*) > 1)

Mital Mehta

• Oct 12th, 2007

Kasi , you are right but the syntax is Wrong .if u write delete *  it will not work .u have to write like this way delete from test where rowid>(select Min(rowid) from test t where t.ename=test.ename)

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Mohammed Abdul Afroze

• Sep 27th, 2007

A sequence generates a list of unique numbers that identifiy the rows and columns of a table.

eswar

• Jul 31st, 2007

Sequence is nothing but a database object which creates an integer value automatically with out duplicates.

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Samudrala

• Jan 30th, 2015

ANY The ANY comparison condition is used to compare a value to a list or subquery. It must be preceded by =, !=, >, ANY (2000, 3000, 4000); EMPNO SAL ---------- ---------- 7...

Samudrala

• Jan 30th, 2015

ALL The ALL comparison condition is used to compare a value to a list or subquery. It must be preceded by =, !=, >, ALL (2000, 3000, 4000); EMPNO SAL ---------- ---------- 783...

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To put the definition of an entity is an entity is a single person, place, or thing about which data can be stored. That is in other words for example when one wants to store information about STUDENT then it has details like studentno, student name, address for communication, phone number, class of the student and so on. All of these details together is placed in the entity or table called as STUDENT....

Ravi

• Oct 31st, 2017

Set of attribute is called entity

Adarsha

• Aug 18th, 2017

Difference between entity and attributes
entity is the table name
and
attribute is the column name of the table

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gcvpgeek

 Profile Answers by gcvpgeek Questions by gcvpgeek

• Mar 17th, 2009

Use this simple querydelete from table1 where rowid not in (select max(rowid) from table1 group by duplicate_col_name)

srividhya_85

 Profile Answers by srividhya_85 Questions by srividhya_85

• Jul 6th, 2008

Hi,   'X' refers here to the table name and 'a' and 'b' are the alias nameDelete from X a where rowid in (select min(rowid) from X  b  &...

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kishanjha

 Profile Answers by kishanjha Questions by kishanjha

• Feb 26th, 2017

Trigger are different from Constraints.
Both supports data integrity but trigger can be imposed on more than one tables.
Triggers can be used to take table backups and changes logs. Like what was the old value, who updated (user) and when (update time)

munny

• Jul 24th, 2015

Triggers are the stored procedures that are fired when an DB event occur where as Constraints are the checks or the rules that are enforced on data columns to maintain the data integrity. Both can be...

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zelani

 Profile Answers by zelani Questions by zelani

• Jan 12th, 2009

null in c is some garbage value which cannot be predicted . If you are not intialising any value to the variable then null value is present in auto variables.null in oracle is used in sql queries for ...

symhdl

 Profile Answers by symhdl Questions by symhdl

• Jan 3rd, 2009

This is not truely the right answer.When you store data in oracle its terminated with a zero byte. For example when you store HELLO its stored as 5HELLO where is the zero byte. When you don...

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