Oracle Error PLS-00326: IN clause must contain same number of expressions as subquery

Oracle Error Message

PLS-00326: IN clause must contain same number of expressions as subquery

Reason for the Error

The number of expressions in an IN clause did not equal the number of expressions in a corresponding subquery select list. For example, the following statement is invalid because the IN clause contains two expressions, but the subquery select list contains just one: … WHERE (ename, sal) IN (SELECT sal FROM emp);

Solution

Check the number of expressions in each set, then revise the statement to make the numbers equal.