Question

我已经制作了以下SQL语句，它不起作用，也无法弄清楚如何创建一个正常的语句。这是我想要做的。

检查玩家表中是否存在值
如果值存在，我想将ignore插入名册表
如果该值不存在，我想将其插入到播放器表中并将其插入到名册表中

这是我的

Intersects(a.span,b.span)

感谢任何帮助！

我尝试了另一种没有运气的尝试

IF EXISTS (SELECT id AS plyrId FROM players WHERE email = @(:e) LIMIT 1)
BEGIN
    INSERT IGNORE INTO roster
        (date, teamId, playerId)
    VALUES
        ( (:d), (:t), plyrId )
END
ELSE
BEGIN
    INSERT INTO players 
        (status, date, first_name, last_name, email) 
    VALUES 
        ( (:s), (:d), (:f), (:l), (:e) )

    INSERT IGNORE INTO roster
        (date, teamId, playerId)
    VALUES
        ( (:d), (:t), LAST_INSERT_ID() )  //LAST_INSERT_ID() -> I want it to be pulled from the last id inserted from the players table - not sure how to accomplish this
END

Answer 1

您必须在插入

之前在事件上使用触发器
CREATE TRIGGER test_trigger BEFORE INSERT ON `players table` FOR EACH ROW SET -- checking value exist or not, for each case write corresponding insert or inserts

Answer 2

这部分查询非常可疑：

IF EXISTS (SELECT id AS plyrId FROM players WHERE email = @(:e) LIMIT 1)
BEGIN
    INSERT IGNORE INTO roster
        (date, teamId, playerId)
    VALUES
        ( (:d), (:t), plyrId )
----------------------^
END

除非你有一个名为plyrId的变量，否则这将失败。在子查询中分配别名不会在外部查询中定义变量。

您可以将其替换为：

INSERT IGNORE INTO roster(date, teamId, playerId)
    SELECT (:d), (:t), id 
    FROM players
    WHERE email = @(:e)
    LIMIT 1;

或者，您可以将if更改为：

IF EXISTS (SELECT plyrdId := id FROM players WHERE email = @(:e) LIMIT 1)

MySQL如果存在插入id，则插入到两个表中

2 个答案: