Correlated Sub Queries.

Unlike the normal Subqueries, the Correlated Subqueries can also be defined as Inner Query embedded in an Outer Query.

But the main difference between Correlated and Uncorrelated or normal Subquery is –

Correlated Subquery Uncorrelated Subquery
Inner Query cannot execute independently of the outer query i.e. it is dependent on Outer query for its execution Inner Query can execute independently of the outer query i.e. it is not dependent on Outer query for its execution
In this Outer Query is executed first , Inner query execution depends upon results of outer query./td>

In this Inner Query is executed first, Outer query depends upon the resultset of outer query .

 

Print Friendly, PDF & Email
Sub Queries [ Uncorrelated Sub Queries ]
Joins
Shikha Katariya

Shikha Katariya

Shikha Katariya ,the Blog author is QA Engineer by profession,Currently serving in MNC, She has more than 4 years of experience in software industry and has worked for domains like Insurance , Core & retail Banking. Always keen to learn new technologies , she has working experience in mainframes,informatica ,and ETL Testing.

You may also like...

Leave a Reply

Your email address will not be published. Required fields are marked *