如何使触发器失效，但是不删除触发器，然后又如何使无效的触发器激活
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禁用并重新启用触发器
下例使用 ALTER TABLE 的 DISABLE TRIGGER 选项来禁用触发器，以使正常情况下会违反触发器条件的插入操作得以执行。然后下例使用 ENABLE TRIGGER 重新启用触发器。
CREATE TABLE trig_example
(id INT,
name VARCHAR(20),
salary MONEY)
go
-- Create the trigger.
CREATE TRIGGER trig1 ON trig_example FOR INSERT
as
IF (SELECT COUNT(*) FROM INSERTED
WHERE salary > 100000) > 0
BEGIN
print 'TRIG1 Error: you attempted to insert a salary > $100,000'
ROLLBACK TRANSACTION
END
GO
-- Attempt an insert that violates the trigger.
INSERT INTO trig_example VALUES (1,'Pat Smith',100001)
GO
-- Disable the trigger.
ALTER TABLE trig_example DISABLE TRIGGER trig1
GO
-- Attempt an insert that would normally violate the trigger
INSERT INTO trig_example VALUES (2,'Chuck Jones',100001)
GO
-- Re-enable the trigger.
ALTER TABLE trig_example ENABLE TRIGGER trig1
GO
-- Attempt an insert that violates the trigger.
INSERT INTO trig_example VALUES (3,'Mary Booth',100001)
GO