update xxx set a=1 where a=2;
update xxx set a=2 where a=3;
update xxx set a=3 where a=4;
三條 sql 整合成一條
UPDATE x
SET a =
CASE
WHEN a=1 THEN 2
WHEN a=2 THEN 3
WHEN a=4 THEN 4
ELSE a
END
update xxx set a=1 where a=2;
update xxx set a=2 where a=3;
update xxx set a=3 where a=4;
三條 sql 整合成一條
UPDATE x
SET a =
CASE
WHEN a=1 THEN 2
WHEN a=2 THEN 3
WHEN a=4 THEN 4
ELSE a
END