¼±£¡£¡£¡Oracle ²¢·¢¿ØÖÆÎÊÌâ
ÎÒÓÐÒ»¸ö´æ´¢¹ý³Ì£¬Æä¹¦ÄÜÊÇͨ¹ýselectÓï¾ä²éÕÒÒ»¸ö±íAÖÐÊÇ·ñÓÐÏàÓ¦µÄ¼Ç¼£¬Èç¹ûûÓÐÔò½øÐвåÈë²Ù×÷£¬È»ºóÎÒÓöà¸öÏ̲߳¢·¢µÄÈ¥µ÷Óô˴洢¹ý³Ì£¬ÓÉÓÚ¶à¸öÏß³ÌͬʱִÐÐselectÓï¾ä£¬¶¼ÒÔΪ±íAÖÐûÓÐÏàÓ¦µÄ¼Ç¼£¬È»ºó¶¼È¥Ö´ÐвåÈë²Ù×÷£¬Ôì³ÉÖØ¸´²åÈ룬Çë½Ì¸ßÊÖ´ËÎÊÌâÈçºÎ½â¾ö£¿ÔÚÏߵȣ¡£¡£¡£¡£¡
ÔÚ¸ÃÁÐÉϼӸöÖ÷¼üÔ¼Êø»òÕßÎ¨Ò»Ô¼Êø¾ÍÐÐÁËô Äã¿ÉÒÔÓÃselect ... for update no waitÓï¾ä ÓÉÓÚijЩÔÒò²»ÄÜÔÚijÁÐÉϼÓÖ÷¼ü»òÕßÎ¨Ò»Ô¼Êø£¬ÎÒÏ£Íûͨ¹ý²¢·¢¿ØÖƵķ½·¨À´½â¾öЩÎÊÌâ ʹÓÃselect ... for update no wait¿ÉÒÔʵÏÖÒ»¸öÏß³ÌÔÚ¶ÁµÄʱºòÆäËüµÄÏ̲߳»ÄܶÁÂ𣿠ÄÇÄãÖ»ÄÜÏñÂ¥ÉÏ˵µÄÄÇÑù£¬Ëø±íÁË¡£ no waitµÄ»°£¬Ò»¸öÏß³ÌËø×¡ÁË£¬ÆäËûÏ̲߳»µÈ´ý£¬Ö±½Ó·µ»ØËø±íʧ°Ü¡£ ÊÇ˵һ¸öÏß³ÌËø×¡ÁË£¬ÄÇôÆäËûÏß³ÌÖ±½Ó·µ»ØÊ§°ÜÂð£¿ÓÐûÓÐʲô°ì·¨²»ÈÃÆäËüÏß³Ìʧ°Ü£¬¶øÊÇÈÃÕâЩÏ̴߳®ÐеÄÖ´ÐÐÕâ¸ö´æ´¢¹ý³Ì£¬¼´µÚÒ»¸öÖ´ÐÐselectÓï¾äµÄỊ̈߳¬ÔÚÖ´ÐÐÍêinsert֮ǰ£¬ÆäËüÏß³ÌÏȲ»Ö´ÐÐselectÄØ£¿»òÊÇÓÐʲôÆäËü·½·¨£¬ÄÜÈø÷¸öÏ̶߳¼ÄÜÕýÈ·Ö´ÐС£ ¼ÓÓÍÒýÓà ÊÇ˵һ¸öÏß³ÌËø×¡ÁË£¬ÄÇôÆäËûÏß³ÌÖ±½Ó·µ»ØÊ§°ÜÂð£¿ÓÐûÓÐʲô°ì·¨²»ÈÃÆäËüÏß³Ìʧ°Ü£¬¶øÊÇÈÃÕâЩÏ̴߳®ÐеÄÖ´ÐÐÕâ¸ö´æ´¢¹ý³Ì£¬¼´µÚÒ»¸öÖ´ÐÐselectÓï¾äµÄỊ̈߳¬ÔÚÖ´ÐÐÍêinsert֮ǰ£¬ÆäËüÏß³ÌÏȲ»Ö´ÐÐselectÄØ£¿»òÊÇÓÐʲôÆäËü·½·¨£¬ÄÜÈø÷¸öÏ̶߳¼ÄÜÕýÈ·Ö´ÐС£ ÄǾͲ»Òªno wait£¬Ö±½Ó select * from table for update£¬Ëø×¡±í£¬²»commit£¬ÆäËûÏ̻߳áÒ»Ö±µÈ´ý¡£µ«ÒªÐ¡ÐļǵÃcommit»òrollback£¬Òª²»¾Í»áËÀËø¡£ ´óÖÂÃ÷°×ʲôÒâ˼ÁË£¬²»¹ýÎÒ»¹ÓÐÒ»µãµãÒÉÎÊ£¬¾ÍÊǵ±Ò»¸öÏß³ÌÖ´ÐÐselectÓï¾ä²¢½øÐÐË
Ïà¹ØÎÊ´ð£º
ÎÒÊÇÓÃÔ¶³Ì×ÀÃæÁ¬²Ù×÷·þÎñÆ÷ÉϵÄÊý¾Ý¿â¡£ ÔÚ´´½¨Ò»¸öÓû§Ö®ºó£¬ÔÙÓÃPLSQLµÇ¼£¬ÔòPLSQLËÀµôÁË¡£ ÎҹصôPLSQLÖ®ºó£¬ÓÃÆäËûÓû§Ò²²»ÄܵǼ¡£ ÎÒ°ÑoracleµÄ·þÎñÍ£Ö¹£¬½á¹û¾ÍÊÇoracleµÄ·þÎñ״̬¾ÍÍ£ÁôÔÚ¡°Í ......
¸÷λoracle¸ßÊÖ£¬Çë½ÌÒ»ÏÂΪʲôoracle 10gÔÚ°²×°µ½°Ù·ÖÖ®°ËÊ®ÎåµÄʱºò¾Í±¨´í²»ÄܼÌÐø°²×°£¿ ÄÚ´æ¶à´ó£¿¡¡ÖØÐÂϸöÊý¾Ý¿â°²×°ÊÔÊÔ.. ÒýÓà ¸÷λoracle¸ßÊÖ£¬Çë½ÌÒ»ÏÂΪʲôoracle 10gÔÚ°²×°µ½°Ù·ÖÖ®°ËÊ®ÎåµÄʱ ......
¼ÙÉètable01 ÖÐÓÐ ÒÔÏÂ×ÊÁÏ emp_no emp_name ------- ------------ 0001 TOM 0002 JOHN 0003 MARY ³£Óõ绰 ¶øÎÒÃÇÒªµÃµ½ÒÔϵÄOUTPUT (»òÊǸ÷ÖÖÆäËûµÄoutput) 0001,TOM 0002,JOHN
......
ÎÊÌâÌá³ö£º Ò»¸ö¸ß¼¶SQLÓï¾äÎÊÌâ ¼ÙÉèÓÐÒ»ÕÅ±í£¬AºÍB×ֶζ¼ÊÇNUMBER£¬ A B 1 2 2 3 3 4 4 ÓÐÕâÑùһЩÊý¾Ý ÏÖÔÚÏëÓÃÒ»ÌõSQLÓï¾ä£¬²éѯ³öÕâÑùµÄÊý¾Ý COLA COL1 COL3 COL2 COL1 4 4 ......