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delete from temp where id not IN (select min(id) from temp group by col1,col2)
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with a as
(select row_number() over (partition by col1,col2 order by col1,col2) as rid,* from temp
)
delete a where rid>1
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ÔÚWindows2003ϰ²×°SQL Server 2000

     ÔÚwindows2003ÏÂÃæ°²×°SQL Server2000£¬»áÌáʾwindows²»Ö§³ÖSQL Server2000µÄ°æ±¾£¬°²×°ºó£¬ÔÚ±¾»úÊÇ¿ÉÒÔÕý³£Ê¹Óõ쬵«ÊÇÎÞ·¨Á¬½Óµ½ÆäËûSQL Server2000µÄ·þÎñÆ÷£¬Ò²ÎÞ·¨Í¨¹ýÆäËû»úÆ÷ÉϵÄSQL Server2000·ÃÎÊ£¬±ØÐë°²×°SQL Server2000sp3»òsp4²¹¶¡²Å¿ÉÒÔ¡£ÆäʵÓÃSQL Server2005¾ÍûÕâôÂé·³ÁË¡£ ......

SQL Group By Top ʵÏÖ

DECLARE @temp TABLE(
id INT,
[name] VARCHAR(50),
class VARCHAR(50)
)
INSERT INTO @temp
SELECT 1,'a','A'
UNION ALL SELECT 2,'b','C'
UNION ALL SELECT 3,'c','B'
UNION ALL SELECT 4,'d','C'
UNION ALL SELECT 5,'e','B'
UNION ALL SELECT 6,'f','A'
SELECT * from @temp AS _temp WHERE [name] IN
( ......

¼òµ¥µÄ3¸öSQLÊÓͼ¸ã¶¨ËùÓÐSqlServerÊý¾Ý¿â×Öµä ת

Êý¾Ý¿â×Öµä°üÀ¨±í½á¹¹(·Ö2KºÍ2005£©¡¢Ë÷ÒýºÍÖ÷¼ü.Íâ¼ü.Ô¼Êø.ÊÓͼ.º¯Êý.´æ´¢¹ý³Ì.´¥·¢Æ÷.¹æÔò¡£¿ÉÒÔÔÚÆóÒµ¹ÜÀíÆ÷¡¢²éѯ·ÖÎöÆ÷Öмòµ¥Ö´ÐУ¬Ö±½ÓÁ˵±µÄ²é³öSQL2K¼°SQL2005µÄËùÓÐÊý¾Ý×ֵ䣬·½±ãÎĵµµÄ±àд£¬Ï£Íû¶Ô´ó¼ÒÓаïÖú¡£
1. SqlServer2000Êý¾Ý¿â×Öµä--±í½á¹¹.sql
SELECT TOP 100 PERCENT --a.id,
   & ......

SQL ServerÖеÄT SQLµÄ»ù±¾¶ÔÏó


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db2 V8µÄÓйØSQL limits

The following tables describe certain SQL
limits. Adhering to the most restrictive case can help the programmer
design application programs that are easily portable.
Table 7. Identifier Length Limits
Description
Limit in Bytes
Longest authorization
name (can only be single-byte characters) ......
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