Sql server 将oracle触发器转换为ms sql触发器
我有一个oracle触发器:Sql server 将oracle触发器转换为ms sql触发器,sql-server,oracle,triggers,Sql Server,Oracle,Triggers,我有一个oracle触发器: CREATE OR REPLACE TRIGGER "BI_Info" BEFORE INSERT ON "Info" FOR EACH ROW WHEN (NEW."Id" IS NULL OR NEW."Id" = 0) BEGIN SELECT NVL(MAX("Id")+1, 1) INTO :NEW."Id" FROM "Info"; END; 现在我想把它转换成ms sql触发器 我知道[Id][int]IDENTITY1,1可以类似地实
CREATE OR REPLACE TRIGGER "BI_Info"
BEFORE INSERT ON "Info" FOR EACH ROW
WHEN (NEW."Id" IS NULL OR NEW."Id" = 0) BEGIN
SELECT NVL(MAX("Id")+1, 1) INTO :NEW."Id" FROM "Info";
END;
现在我想把它转换成ms sql触发器
我知道[Id][int]IDENTITY1,1可以类似地实现此触发器
但我不希望Id自动添加一个
谢谢
MS SQL不支持BEFORE触发器。您应该使用而不是触发器。
MS SQL触发器是基于集合的而不是基于行的触发器,因此应该考虑到这一点
尽管如此,你还是可以试一试
CREATE TRIGGER tg_BI_Info_insert ON BI_Info
INSTEAD OF INSERT AS
BEGIN
DECLARE @max INT
SET @max = (SELECT COALESCE(MAX(id), 0) FROM BI_Info WITH (TABLOCKX, HOLDLOCK))
INSERT INTO BI_Info (id, column1, ...)
SELECT @max + ROW_NUMBER() OVER (ORDER BY (SELECT 1)), column1, ...
FROM INSERTED
END
这是演示
如果希望在NEW.Id为NULL或NEW.Id=0时模拟部件,允许插入显式分配的Id,则
CREATE TRIGGER tg_BI_Info_insert ON BI_Info
INSTEAD OF INSERT AS
BEGIN
DECLARE @max INT
INSERT INTO BI_Info
SELECT *
FROM INSERTED
WHERE COALESCE(id, 0) <> 0
SET @max = (SELECT COALESCE(MAX(id), 0) FROM BI_Info WITH (TABLOCKX, HOLDLOCK))
INSERT INTO BI_Info (id, column1)
SELECT @max + ROW_NUMBER() OVER (ORDER BY (SELECT 1)), column1
FROM INSERTED
WHERE COALESCE(id, 0) = 0
END
下面是这种情况的演示NVL函数的作用是什么?检查Id是否为空