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Column1 Âú×ãvalue1
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Column2 Âú×ãvalue2
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Column3 Âú×ãvalue3
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SELECT top 10 * from TABLE1
WHERE
CASE WHEN COLUMN1='value1' THEN 1
ELSE
(CASE WHEN COLUMN2='value2' THEN 1
ELSE
(CASE WHEN COLUMN3=value3 THEN 1 ELSE 0 END)
END)
END =1


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"Select * from users where name='"+uName+"' and pwd='"+uPwd+"' " ......

oracle sql tuning

alert index mem_ct monitoring usage;
desc v$object_usage;
set linesize 190
select * from v$object_usage;
SQL>SET AUTOTRACE ON;
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¡¡¡¡SQL> set timing on;
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SQL ServerÈÕÆÚ²Ù×÷

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select * from [tablename] where date between \'value1\' and \'value2\'
 
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select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b
 
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select * from Èճ̰²ÅÅ w ......

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2010-05-05 13:35:52.06 Server Microsoft SQL Server 2005 - 9.00.1399.06 (Intel X86)
Oct 14 2005 00:33:37
Copyright (c) 1988-2005 Microsoft Corporation
Developer Edition on Windows NT 5.1 (Build 2600: Service Pack 3)
2010-05-05 13:35:52.06 Server (c) 2005 Microsoft Corporation.
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SQL ɾ³ýÖØ¸´Êý¾Ý£¬Ö»±£Áô1Ìõ

if not object_id('Tempdb..#T') is null
    drop table #T
Go
Create table #T([ID] int,[Name] nvarchar(1),[Memo] nvarchar(2))
Insert #T
select 1,N'A',N'A1' union all
select 2,N'A',N'A2' union all
select 3,N'A',N'A3' union all
select 4,N'B',N'B1' union all
select 5,N'B',N'B2'
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