Also, the CASE statement cannot have an ELSE NULL clause (the CASE operator can), and it is terminated with END CASE instead of END (which is how the CASE operator is terminated). The CASE statement is specifically for use in stored programs. The CASE OperatorĪs mentioned, in MySQL there’s a difference between the CASE statement and the CASE operator. CASE Avalue WHEN Bvalue THEN Bstatement WHEN CValue THEN Cstatement. As an alternative to general SQL statement, sometimes you can use built-in MySQL function to help in some. This value is compared to the whenvalue expression in each WHEN clause until one of them is equal. PHP & MySQL Using SUM and CASE in statement. See the MySQL CASE operator for an example of how the second syntax (the searched CASE expression) works. MySQL Query Comparing with value, Syntax is here. For the first syntax, casevalue is an expression. Now when we call that procedure, the output depends on our input: CALL sp_lunch( 'Thai', ) Īnd with different input: CALL sp_lunch( 'Italian', ) Īnd when we input a value that’s not covered by any of the WHEN conditions, the ELSE clause is effected: CALL sp_lunch( 'Aussie', ) The simple CASE expression compares an expression to a set of simple expressions to determine the result. This syntax is referred to as the simple CASE expression. Here’s an example of a basic stored procedure with the first CASE syntax: DELIMITER | WHEN search_condition THEN statement_list The CASE statement can be used in two ways. Also, there’s a slight difference in the syntax. The CASE statement is different to the CASE operator, in that the CASE statement is specifically for use in stored programs. It compares a list of conditions and returns a different result depending on which condition (if any) is matched. In MySQL, the CASE statement can be used in stored programs to perform a complex conditional construct.
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