mysql Ò»ÌõsqlÓï¾äupdate¸üÐÂÁ½¸ö±í
Äãд¹ýÒ»ÌõsqlÓï¾äÀ´ÐÞ¸ÄÁ½¸ö±íµÄÊý¾ÝÂð£¿
UPDATE test.table1 t1,test.table2 t2 SET t1.aa='a',t1.bb='b',t2.cc='c',WHERE t1.u_id=t2.u_id AND t1.u_id='1' £»
table1µÄu_idºÍtable2µÄu_idÊÇÖ÷Íâ¼ü¹ØÏµ
Ïà¹ØÎĵµ£º
±íÖÐÖ÷¼ü±ØÐëΪ±êʶÁУ¬[ID] int IDENTITY (1,1)
1.·ÖÒ³·½°¸Ò»£º(ÀûÓÃNot InºÍSELECT TOP·ÖÒ³)
Óï¾äÐÎʽ£º
SELECT TOP Ò³¼Ç¼ÊýÁ¿ *
from ±íÃû
WHERE (ID NOT IN
(SELECT TOP (ÿҳÐÐÊý*(Ò³Êý-1)) ID
from ±íÃû
ORDER BY ID))
ORDER BY ID
//×Ô¼º»¹¿ÉÒÔ¼ÓÉÏһЩ²éѯ ......
±íÖÐÖ÷¼ü±ØÐëΪ±êʶÁУ¬[ID] int IDENTITY (1,1)
1.·ÖÒ³·½°¸Ò»£º(ÀûÓÃNot InºÍSELECT TOP·ÖÒ³)
Óï¾äÐÎʽ£º
SELECT TOP Ò³¼Ç¼ÊýÁ¿ *
from ±íÃû
WHERE (ID NOT IN
(SELECT TOP (ÿҳÐÐÊý*(Ò³Êý-1)) ID
from ±íÃû
ORDER BY ID))
ORDER BY ID
//×Ô¼º»¹¿ÉÒÔ¼ÓÉÏһЩ²é ......
Èç¹û°´ÕÕpowerdesignerµÄĬÈÏÑ¡Ïî,Éú³ÉµÄsql²»ÄÜÔÚmysqlÖÐÕýÈ·ÔËÐÐ.]
¾¹ý±¾ÈËÑо¿·¢ÏÖÒª×öÈçÏÂÐÞ¸Ä:
1.aftercreateÑ¡Ïî¸ÄΪ
.foreach_item(OutReferences)
.ifnot (%hasFKIndex%)
/*==============================================================*/
/* Index: ......
´Ó8iµ½10g£¬Oracle²»¶Ï½ø»¯×Ô¼ºµÄSQL TuningÖÇÄÜ£¬Ò»Ð©Ãؼ®¼¶µÄÓÅ»¯¿Ú¾÷ÒѾʧЧ¡£
µ«ÎÒϲ»¶Ê§Ð§£¬²»Óüǿھ÷£¬²Ù¸öToad for Oracle Xpert
£¬°´ÕÕ´ó·½ÏòÊæÊæ·þ·þµÄ
µ÷ÓŲÅÊǰ®×öµÄÊÂÇé¡£
1.Excution Plan
Excution
PlanÊÇ×î»ù±¾µÄµ÷ÓŸÅÄ²»¹ÜÄãµÄµ÷ÓÅ´µµÃÈçºÎÌ ......