Difference between sub query and nested query ?

Answer Posted / vrushali

Co-related sub query is one in which inner query is
evaluated only once and from that result outer query is
evaluated.

Nested query is one in which Inner query is evaluated for
multiple times for gatting one row of that outer query.

ex. Query used with IN() clause is Co-related query.
Query used with = operator is Nested query

Is This Answer Correct ?    8 Yes 68 No



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