• 如何在MySQL做以下发言?
UPDATE my_table t1 SET column_1 =
(SELECT column_1 FROM my_table t2 WHERE t2.id = (t1.id - 1))
WHERE t1.type = 2
我正在读到<代码>”。 您可具体说明从“错误中删除的具体目标表1。
你可以加入:
UPDATE my_table t1
JOIN my_table t2 ON t2.id = t1.id - 1
SET t1.column_1 = t2.column_1
WHERE t1.type = 2
拆除“米-表”:
UPDATE t1 SET column_1 =
(SELECT column_1 FROM t2 WHERE t2.id = (t1.id - 1))
WHERE t1.type = 2
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