USE `db`;
DROP PROCEDURE IF EXISTS schema_change;
DELIMITER //
CREATE PROCEDURE schema_change() BEGIN
DECLARE CurrentDatabase VARCHAR(100);
SELECT DATABASE() INTO CurrentDatabase;
IF NOT EXISTS (SELECT * FROM information_schema.columns WHERE table_schema=CurrentDatabase AND table_name = 'FILE_PATH_TABLE' AND column_name = 'FILE_NAME') THEN
ALTER TABLE FILE_PATH_TABLE ADD FILE_NAME VARCHAR(2000) NULL DEFAULT NULL COMMENT '文件名称';
END IF;
END//
DELIMITER ;
CALL schema_change();
DROP PROCEDURE IF EXISTS schema_change;
DELIMITER //
CREATE PROCEDURE schema_change() BEGIN
DECLARE CurrentDatabase VARCHAR(100);
SELECT DATABASE() INTO CurrentDatabase;
IF NOT EXISTS (SELECT * FROM information_schema.columns WHERE table_schema=CurrentDatabase AND table_name = 'FILE_PATH_TABLE' AND column_name = 'FILE_NAME') THEN
ALTER TABLE FILE_PATH_TABLE ADD FILE_NAME VARCHAR(2000) NULL DEFAULT NULL COMMENT '文件名称';
END IF;
END//
DELIMITER ;
CALL schema_change();