Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

Ëæ»úÑ¡ÔñÐеÄSQLÓï¾ä? ORACLE SQLSERVER ECT.

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 Tim
Oracle:
SELECT column from
( SELECT column from table
ORDER BY dbms_random.value )
WHERE rownum = 1
Thanks Mark Murphy
Feel free to post other example, variations, and SQL statements for other database servers in the comments.


Ïà¹ØÎĵµ£º

oracle´¥·¢Æ÷

´¥·¢Æ÷ÊÇÒ»ÖÖÌØÊâµÄ´æ´¢¹ý³Ì£¬ËüÔÚ²åÈ룬ɾ³ý»òÐÞ¸ÄÌØ¶¨±íÖеÄÊý¾Ýʱ´¥·¢Ö´ÐУ¬Ëü±ÈÊý¾Ý¿â±¾Éí±ê×¼µÄ¹¦ÄÜÓиü¾«Ï¸ºÍ¸ü¸´ÔÓµÄÊý¾Ý¿ØÖÆÄÜÁ¦¡£Êý¾Ý¿â´¥·¢Æ÷ÓÐÒÔϵÄ×÷Óãº
¡¡¡¡* °²È«ÐÔ¡£¿ÉÒÔ»ùÓÚÊý¾Ý¿âµÄֵʹÓû§¾ßÓвÙ×÷Êý¾Ý¿âµÄijÖÖȨÀû¡£
¡¡¡¡# ¿ÉÒÔ»ùÓÚʱ¼äÏÞÖÆÓû§µÄ²Ù×÷£¬ÀýÈç²»ÔÊÐíϰàºóºÍ½Ú¼ÙÈÕÐÞ¸ÄÊý¾Ý¿âÊý¾Ý¡£ ......

OracleÖÐNullÓë¿Õ×Ö·û´®''µÄÇø±ð

¾­²âÊÔ£¬ÔÚOracleÖУ¬¶ÔÓÚnullºÍ¿Õ×Ö·û´®'',webMethods JDBC Adapter ²éѯ³öÀ´¶¼»áÏÔʾnull.
¶øÔÚSQL SERVERÖУ¬»á·Ö±ðÏÖʵΪnullºÍ¿Õ×Ö·û´®¡£
º¬Òå½âÊÍ£º
ÎÊ£ºÊ²Ã´ÊÇNULL£¿
´ð£ºÔÚÎÒÃDz»ÖªµÀ¾ßÌåÓÐʲôÊý¾ÝµÄʱºò£¬Ò²¼´Î´Öª£¬¿ÉÒÔÓÃNULL£¬ÎÒÃdzÆËüΪ¿Õ£¬ORACLEÖУ¬º¬ÓпÕÖµµÄ±íÁ㤶ÈΪÁã¡£
ORACLEÔÊÐíÈκÎÒ»ÖÖÊý¾ ......

ת:Oracleϵͳ·Ç¿ÕÏеȴýʼþ

select sid,
       p1,
       p1raw,
       p2,
       p2raw,
       p3,
       p3raw,
    &n ......

½éÉÜSQL Server 2005µÄCROSS Apply

Cross Applyʹ±í¿ÉÒԺͱíÖµº¯Êý½á¹û½øÐÐjoin, ÕâÑù±íÖµº¯ÊýµÄ²ÎÊý¾Í¿ÉÒÔʹÓÃÒ»¸ö½á¹û¼¯£¬¶ø²»ÊÇÒ»¸ö±êÁ¿Öµ£¬ÏÂÃæÊÇbook onlineµÄÔ­ÎÄ£¬ÓÐÀý×Ó£¬ÓнâÊÍ¡£
The APPLY operator allows you to invoke a table-valued function for each row returned by an outer table expression of a query. The table-valued function act ......

SQL Server 2005ÖÐÐÂÔöµÄ¹¦ÄÜÇ¿´óµÄ´°¿Úº¯Êý

Ô­ÎĵØÖ·£ºhttp://www.cnblogs.com/changhai0605/articles/1276319.html
OracleµÄÇë²Î¿¼£ºhttp://zonghl8006.blog.163.com/blog/static/4528311520083995931317/
1.¼ò½é£º
SQL Server 2005ÖÐÐÂÔöµÄ´°¿Úº¯Êý°ïÖúÄãѸËٲ鿴²»Í¬¼¶±ðµÄ¾ÛºÏ£¬Í¨¹ýËü¿ÉÒԷdz£·½±ãµØÀÛ¼Æ×ÜÊý¡¢Òƶ¯Æ½¾ùÖµ¡¢ÒÔ¼°Ö´ÐÐÆäËü¼ÆËã¡£
´°¿Úº¯Êý¹¦ÄÜ·Ç ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ