我在 mysql create function 语句中遇到错误

Question

DROP FUNCTION IF EXISTS PortName;
CREATE FUNCTION PortName(port INT) RETURNS VARCHAR(3) CHARSET latin1
BEGIN
    DECLARE x VARCHAR(3);
    CASE port;
       WHEN 996 THEN SET x = 'RP';
       WHEN 995 THEN SET x = 'IA';
       WHEN 990 THEN SET x = 'K1';
       WHEN 989 THEN SET x = 'K2';
       WHEN 988 THEN SET x = 'K3';
       WHEN 986 THEN SET x = 'NG';
       WHEN 985 THEN SET x = 'NW';
       WHEN 984 THEN SET x = 'N2';
       WHEN 983 THEN SET x = 'N3';
       ELSE SET x = 'NA';
    RETURN x;
END;

Answer 1

CASE port 和 WHEN 语句之间不应有 ;。最后你需要END CASE;。

DROP FUNCTION IF EXISTS PortName;
CREATE FUNCTION PortName(port INT) RETURNS VARCHAR(3) CHARSET latin1
BEGIN
    DECLARE x VARCHAR(3);
    CASE port
       WHEN 996 THEN SET x = 'RP';
       WHEN 995 THEN SET x = 'IA';
       WHEN 990 THEN SET x = 'K1';
       WHEN 989 THEN SET x = 'K2';
       WHEN 988 THEN SET x = 'K3';
       WHEN 986 THEN SET x = 'NG';
       WHEN 985 THEN SET x = 'NW';
       WHEN 984 THEN SET x = 'N2';
       WHEN 983 THEN SET x = 'N3';
       ELSE SET x = 'NA';
    END CASE;
    RETURN x;
END;

有关 CASE 的语法，请参见 https://dev.mysql.com/doc/refman/8.0/en/case.html。

我在 mysql create function 语句中遇到错误

I am getting error in mysql create function statement

mysql

mysql-error-1064