oracle中Merge的使用
一.只更新不插入
Merge into Merge_test2 M
Using Merge_test1 N
ON (M.A = N.A)
WHEN MATCHED THEN
UPDATE SET M.B = N.B;
二.只插入不更新
MERGE INTO merge_test2 M
USING merge_test1 N
ON (M.A =N.A)
WHEN NOT MATCHED THEN
INSERT (M.A,M.B) VALUES(N.A,N.B);
三.更新+插入
MERGE INTO merge_test2 M
USING merge_test1 N
ON(M.A = N.A)
WHEN MATCHED THEN
UPDATE SET M.B=N.B
WHEN NOT MATCHED THEN
INSERT (M.A,M.B)VALUES(N.A,N.B)