The following MySQL statement belongs to which condition types?

SELECT fname
FROM person
WHERE dept_id= (SELECT dept_id FROM department WHERE names=’s’);

Solution (By Examveda Team)

This MySQL statement uses a subquery to find the department ID of a department named 's' and then selects all the first names (fname) from the person table where the department ID matches the result of the subquery.
Subquery is a query nested inside another query.
Let's break down the statement:
1. SELECT fname FROM person: This part of the statement selects the first names (fname) from the person table.
2. WHERE dept_id = (SELECT dept_id FROM department WHERE names = 's'): This part of the statement specifies the condition for selecting the first names. It says to select only those first names where the department ID (dept_id) matches the department ID retrieved from the subquery.
3. (SELECT dept_id FROM department WHERE names = 's'): This is the subquery that retrieves the department ID (dept_id) from the department table where the department name (names) is equal to 's'.
Therefore, this statement uses an equality condition to match the department ID retrieved from the subquery.
So the answer is Option A: Equality condition