Where Clause Purpose The Where clause specifies the conditions that rows must meet to be retrieved. Grammar WHERE expr1rel_operatorexpr2 where: expr1 Is either a column name, literal, or expression. expr2 Is either a column name, literal, expression, or subquery. Subqueries must be enclosed in parentheses. rel_operator Is the relational operator that links the two expressions. Example The following Select statement retrieves the first and last names of employees that make at least $20,000. SELECT last_name, first_name FROM emp WHERE salary >= 20000 See also See Subqueries for complete information about subqueries. See SQL Expressions for details about expressions.