SQL-Subqueries(Nested Query)-Page13

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👉Subqueries (Nested Query)

A subquery is a form of an SQL statement that appears inside another SQL statement (Parent statement).

The parent statement uses the rows returned by the subquery.


👉Operator  IN, NOT IN


👉Exists, Not Exists

Exists - If the inner query finds a match, it will produce output.
Not Exists - If it does not find match, it will not produce output.


It checks for each branch, if branch does not exists in EMP_MSTR, it will display that row.

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