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1. ¿ªÆôÒ»¸öÊÂÎñÖ´ÐвåÈëÊý¾ÝµÄ²Ù×÷¡£
BEGIN TRAN t
INSERT INTO Customer
SELECT 'a','a'
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SELECT * from Customer WITH (NOLOCK)
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SELECT * from Customer
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SELECT * from Customer WITH (READPAST)
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BEGIN TRAN t
INSERT INTO Customer
SELECT 'b','b'
COMMIT TRAN t
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NOLOCK
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SELECT * from Customer WITH (NOLOCK)
WAITFOR delay '00:00:20'
COMMIT TRAN ttt
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INSERT INTO Customer SELECT 'a','b' –²»Ëø¶¨
DELETE Customer where ID=1 –²»Ëø¶¨
SELECT * from Customer –²»Ëø¶¨
UPDATE Customer SET Title='aa' WHERE ID=1 –²»Ëø¶¨
ROWLOCK
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SET TRANSACTION ISOLATION LEVEL REPEATABLE READ -- (±ØÐë)
BEGIN TRAN ttt
SELECT * from Customer WITH (ROWLOCK) WHERE ID=17
WAITFOR delay '00:00:20'
COMMIT TRAN ttt
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INSERT INTO Customer SELECT 'a','b' –²»µÈ´ý
DELETE Customer where ID=17 –µÈ´ý
DELETE Customer where ID<>17 –²»µÈ´ý
SELECT * from Customer –²»µÈ´ý
UPDATE Customer SET Title='aa' WHERE ID=17–µÈ´ý
UPDATE Customer SET Title='aa' WHERE ID<>17–²»µÈ´ý
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1. Ö´ÐÐHOLDLOCK
BEGIN TRAN ttt
SELECT * from Customer WITH (HOLDLOCK)
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