MySQL存储过程选择检查插入

Question

因此，我试图在MySQL 5.5版中创建一个存储过程。 我不确定什么是错的，但是我想完成的是。

从表A获取记录，该记录已存在7天了。 然后插入表B，但是我需要检查表B中是否存在。如果存在，则跳过，否则插入。

所以这是我的代码：

DROP PROCEDURE IF EXISTS `move_record`;
DELIMITER //
CREATE PROCEDURE `move_record`()
BEGIN
        DECLARE done INT DEFAULT FALSE;
        DECLARE dt DATETIME;
        DECLARE uid,value BIGINT(20);
        DECLARE category VARCHAR(30);
        DECLARE data,comments VARCHAR(255);
        DECLARE cancel TINYINT(1) DEFAULT NULL;

        DECLARE curs CURSOR FOR SELECT `datetime`,user_id,category,data,comments,cancel FROM `record` WHERE `datetime` < DATE_SUB(CURDATE(), INTERVAL 7 DAY);

        DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

        OPEN curs;

        myloop: LOOP
        FETCH NEXT FROM curs INTO dt,uid,category,data,comments,cancel;
        IF done THEN
            LEAVE myloop;
        END IF;

        IF NOT EXISTS (SELECT * FROM `record_arc`
                        WHERE record_arc.`datetime` = dt
                        AND record.user_id = uid )
        INSERT INTO `record_arc` (`datetime`,user_id,category,data,comments,cancel) VALUES (dt,uid,category,data,comments,cancel);

        END IF;
        END LOOP myloop;

        CLOSE curs;
        DEALLOCATE curs;
END//
DELIMITER ;

Answer 1

也许您可以无循环执行此操作。

INSERT INTO `record_arc`(
    `datetime`,
    user_id,
    category,
    data,
    comments,
    cancel
)
SELECT 
    `datetime`,
    user_id,
    category,
    data,
    comments,
    cancel 
FROM `record` r
WHERE 
    `datetime` < DATE_SUB(CURDATE(), INTERVAL 7 DAY)
    AND NOT EXISTS(
        SELECT 1
        FROM `record_arc` r2
        WHERE
            r2.`datetime` = r.`datetime`
            AND r2.user_id = r.user_id
    )

Answer 2

别名错误地使用了它。 检查以下代码

IF NOT EXISTS (SELECT 1 FROM `record_arc`
                            WHERE record_arc.`datetime` = dt
                            AND record_arc.user_id = uid )