MySQL has an if syntax ( if(action=2 and state=0, 1, 0) ), but case is more universal. Note that the as state there is just aliasing the column. ... <看更多>

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In MySQL, IF statements cannot exist outside of stored procedures. Therefore, to create an idempotent migration for MySQL it's necessary to wrap the ... ... <看更多>

INSERT INTO test (number) SELECT COALESCE(MAX(number), 1) FROM test;. UPDATE. If record(s) exists we need in the next value. So: ... <看更多>