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a  b
10  7
(a-b)=a
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SQL code:
update a set a=a-b

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SQL code:
-->Title:Generating test data
-->Author:wufeng4552
-->Date :2009-10-12 15:12:56

declare @T table([a] int,[b] int)
Insert @T
select 10,7
update @t set [a]=[a]-[b]
select * from @T
/*
a b
----------- -----------
3 7

(1 個資ÁÏÁÐÊܵ½Ó°響)
*/

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SQL code-->Title:Generating test data
-->Author:wufeng4552
-->Date :2009-10-12 15:12:56declare@Ttable([a]int,[b]int)Insert@Tselect10,7update@tset[a]=[a]-[b]select*from@T/*
a          b
----------- -----------
3          7

(1 個資ÁÏÁÐÊܵ½Ó°響)*/

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