Different operators used in building sub queries

What are the different operators used in building sub queries?

Following operators can be used in building sub queries:

IN: Allows multiple values to be checked.

EXIST: Checks if a value exists.

There are other logical operators like AND, OR and comparison operators like =, <, > can also be used.

Example:
Select emp_id, emp_name from employee
Where emp_id IN (select emp_id FROM salary);

What are the different operators used in building sub queries?

IN and NOT IN operator
ANY
ALL
Exists
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