我试图将三个更新语句合并为一个。
"UPDATE DOT_WORKS SET START_DATE = :StartDate WHERE ID = :WorksId and END_DATE IS NULL;"
"UPDATE DOT_WORKS SET WORKS_TYPE = :WorksType WHERE ID = WorksId and WORKS_GROUP = :WorksGroup;"
"UPDATE DOT_WORKS SET WORKS_CONNECTION = :WorksConn WHERE ID = WorksId and WORKS_PLACE = :WorksPlace;"
我想知道是否有办法做到这一点。 我尝试这样做的原因是为了保存对数据库的调用。调用db一次而不是三次更有效。
谢谢!
答案 0 :(得分:2)
UPDATE DOT_WORKS
SET START_DATE = case when END_DATE IS NULL then :StartDate else START_DATE end,
WORKS_TYPE = case when WORKS_GROUP = :WorksGroup then :WorksType else WORKS_TYPE end,
WORKS_CONNECTION = case when WORKS_PLACE = :WorksPlace then :WorksConn else WORKS_CONNECTION end
WHERE ID = :WorksId
and
(
END_DATE IS NULL OR
WORKS_GROUP = :WorksGroup OR
WORKS_PLACE = :WorksPlace
)