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SET TRANSACTION ISOLATION LEVEL REPEATABLE READ

begin tran

select * from tablename with (rowlock) where id=3

waitfor delay '00:00:05'

commit tran

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update tablename set colname='10' where id=3 --ÔòÒªµÈ´ý5Ãë

update tablename set colname='10' where id<>3 --¿ÉÁ¢¼´Ö´ÐÐ

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SELECT * from table WITH (HOLDLOCK)


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SELECT * from table WITH (HOLDLOCK)
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SELECT * from table WITH (TABLOCKX)
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SQL code:

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select @cnt=count(1) from TableTest
if(@cnt==0)
insert into TableTest values(1,'abc')


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