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http://www.cnblogs.com/yinzhenzhixin/archive/2009/01/07/1371064.html
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SELECT [Id],[Name],[Comment] from [Product1]
UNION
SELECT [Id],[Name],[Comment] from [Product2]
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SELECT [Id],[Name],[Comment] from [Product1] WHERE LEN([Name]) > 5
UNION
SELECT [Id],[Name],[Comment] from [Product2] WHERE [Id] IN (11,20) AND [Comment] IS NOT NULL
SELECT TOP N [Id],[Name],[Comment] from [Product1]
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product2]
This is so easy£¡µ«ÊǼÙÈçÄúÏ£Íû´Ó°üº¬Type×ֶεÄij±íÖиù¾ÝType·Ö±ðËæ»úɸѡNÌõ¼Ç¼²¢½«½á¹ûºÏ²¢³ÉÒ»ÕÅ±í£¬Äú¿ÉÄÜ»áÏñÏÂÃæÕâÑùд£º
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE1' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE2' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE3' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE4' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE5' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE6' ORDER BY NEWID()
UNION
SELECT TOP N [Id],[Name],[Comment] from [Product] WHERE [Type]='TYPE7' ORDER BY NEW
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MySQL:
SELECT column from table
ORDER BY RAND()
LIMIT 1
PostgreSQL:
SELECT column from table
ORDER BY RANDOM()
LIMIT 1
Microsoft SQL Server:
SELECT TOP 1 column from table
ORDER BY NEWID()
IBM DB2
SELECT column, RAND() as IDX
from table
ORDER BY IDX FETCH FIRST 1 ROWS ONLY
Thanks Ti ......
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