Hi,
Would you please tell me how a sub-query looks like and a correlated sub-query? Do they always have fixed form of writing it?
Thanks.
a Sub-Query and a Correlated Sub-Query
Moderators: Kalicharan, Moderator Group
a Sub-Query and a Correlated Sub-Query
Arr Bee
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?My joy in learning is partly that it enables me to teach? - Seneca(Roman philosopher, mid-1st century AD)
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?My joy in learning is partly that it enables me to teach? - Seneca(Roman philosopher, mid-1st century AD)
sub query vs correlated sub query
Hi,
You can refer correlated subquery in
http://www.mainframegurukul.com/Mainfra ... php?t=4628
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Example
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Subquery -
Correlated suquery -
Here we are using instance A from outer query in the innerquery, hence we are calling it as correlated subquery.
In normal subquery, we dont have any reference from outer query, being used in the inner query.
You can refer correlated subquery in
http://www.mainframegurukul.com/Mainfra ... php?t=4628
----------
Example
----------
Subquery -
Code: Select all
SELECT * FROM TABLE WHERE
FIELD1 = ( SELECT FIELDA FROM TABLEB )
Code: Select all
SELECT * FROM TABLE A WHERE
FIELD1 = ( SELECT FIELDA FROM TABLEB B WHERE A.FIELD1 = B.FIELDB )
In normal subquery, we dont have any reference from outer query, being used in the inner query.
Natarajan
Chennai
Chennai
inner query?
Hi, Thanks for the reply.
Does inner query execute first or outer query in sub-query / correlated sub-query?
Please explain.
Thanks.
Does inner query execute first or outer query in sub-query / correlated sub-query?
Please explain.
Thanks.
Arr Bee
-------------
?My joy in learning is partly that it enables me to teach? - Seneca(Roman philosopher, mid-1st century AD)
-------------
?My joy in learning is partly that it enables me to teach? - Seneca(Roman philosopher, mid-1st century AD)
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