在 MySQL/InnoDB 中模拟自动增量

DELIMITER //

CREATE PROCEDURE GetNextAutoIncrementValue(IN tableName VARCHAR(255), OUT nextValue INT)
BEGIN
    SET @sql = CONCAT('SELECT AUTO_INCREMENT INTO @nextValue FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = \'', tableName, '\'');
    PREPARE stmt FROM @sql;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;
    SET nextValue = @nextValue;
END //

DELIMITER ;

DELIMITER //

CREATE TRIGGER AutoIncrementTrigger BEFORE INSERT ON tableName
FOR EACH ROW
BEGIN
    DECLARE nextValue INT;
    CALL GetNextAutoIncrementValue('tableName', nextValue);
    SET NEW.columnName = nextValue;
END //

DELIMITER ;