The difference between Where and Having clauses in SQL

In this article, we will understand the difference between WHERE clause and HAVING clause in SQL.

WHERE clause

• It is used to filter records from the table based on specific conditions.

• It can be used without the "GROUP BY" clause.

• It can be used with row operations.

• It cannot contain aggregate functions.

• It can be used with "SELECT", "UPDATE" and "DELETE" statements.

• If required, it can be used before the "GROUP BY" clause.

• It is used with single-line functions (such as "UPPER", "LOWER").

HAVING clause

• It is used to filter records from groups based on specific criteria.

• It cannot be used without the "GROUP BY" clause.

• It is used with column operations.

• It can contain aggregate functions.

• It can only be used with the "SELECT" statement.

• It is used after the "GROUP BY" clause.

• It can be used with multi-line functions (such as "SUM", "COUNT").

The following is the syntax:

SELECT column1, column2
FROM table1, table2
WHERE [ conditions ]
GROUP BY column1, column2
HAVING [ conditions ]
ORDER BY column1, column2

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