mysql 动态where条件查询语句吗

SET @sql = CONCAT('SELECT * FROM users WHERE 1=1');

IF @age IS NOT NULL THEN
    SET @sql = CONCAT(@sql, ' AND age = ', @age);
END IF;

IF @name IS NOT NULL THEN
    SET @sql = CONCAT(@sql, ' AND name LIKE "%', @name, '%"');
END IF;

PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

SET @age = 25;
SET @name = 'John';

SET @sql = 'SELECT * FROM users WHERE 1=1';

IF @age IS NOT NULL THEN
    SET @sql = CONCAT(@sql, ' AND age = ?');
END IF;

IF @name IS NOT NULL THEN
    SET @sql = CONCAT(@sql, ' AND name LIKE ?');
END IF;

PREPARE stmt FROM @sql;
IF @age IS NOT NULL THEN
    SET @bind_age = @age;
    EXECUTE stmt USING @bind_age;
END IF;
IF @name IS NOT NULL THEN
    SET @bind_name = CONCAT('%', @name, '%');
    EXECUTE stmt USING @bind_name;
END IF;
DEALLOCATE PREPARE stmt;