Ö÷¼üºÍÍâ¼ü
ʲôÊÇÖ÷¼üºÍÍâ¼ü?
Ö÷¹Ø¼ü×ÖÊÇÓÃÓÚΨһµØ±êʶ±íÖеÄijһÌõ¼Ç¼¡£ÁªÏµ£ºÍâ¼üÊÇÏà¶ÔÓÚÊý¾Ý¿âÉè¼ÆÖеIJο¼ÍêÕûÐÔ¶øÑÔ£¬ÓëÖ÷¼ü...
Ö÷¼üÓëÍâ¼üµÄ¹Øϵ
Ö÷¼üÊÇΨһ±êʶ±íÖмǼµÄ×ֶΣ¬Íâ¼üÊǽ¨Á¢±íÓë±íÖ®¼ä¹ØϵµÄ×ֶΡ£Ö÷¼üÊǹØϵÊý¾Ý¿âÖÐÓÃÓÚΨһ±êʶ±íÖÐÿһÌõ¼Ç¼µÄ×ֶλò×Ö¶Î×éºÏ¡£
¾ÙÀý˵Ã÷ʲôÊÇÖ÷¼üºÍÍⲿ¼ü. ¨C ÊÖ»ú°®ÎÊ
t_name, t_stu stu_noÊDZístudentµÄÖ÷¼ü±ê,Ψһȷ¶¨Ò»¸öѧÉúÐÅÏ¢,stu_supervisorÊÇÍâ¼ü±ê,È·¶¨Ñ§ÉúµÄµ¼Ê¦ÐÅÏ¢¡£ emp...
ʲôÊÇÖ÷¼üÓëÍâ¼ü?
Íâ¼ü£ºÒÀÀµÓÚ±ðµÄ±íµÄÊý¾Ý£¬Î¨Ò»¼ü£ºÔÚ±íÖÐΨһ¡£\x0d\x0a\x0d\x0aÖ÷¼üºÍΨһ¼üµÄÒ»¸öÇø±ð£º...
ʲôÊÇÖ÷¼üÓëÍâ¼ü
1¡¢Ö÷¼ü£¬ÊDZ»ÌôÑ¡³öÀ´£¬×÷±íµÄÐеÄΩһ±êʶµÄºòÑ¡¹Ø¼ü×Ö¡£Ò»¸ö±íÖ»ÓÐÒ»¸öÖ÷¹Ø¼ü×Ö¡£Ö÷¹Ø¼ü×ÖÓÖ¿ÉÒÔ³ÆΪÖ÷¼ü¡£Ö÷¼ü¿ÉÒÔÓÉÒ»¸ö×Ö...
SQLÊý¾Ý¿âÖеÄÖ÷¼üÓëÍâ¼ü½éÉÜ - °Ù¶È¾Ñé
1 Ò»¡¢Ê²Ã´ÊÇÖ÷¼ü¡¢Íâ¼ü£º¹ØϵÐÍÊý¾Ý¿âÖеÄÒ»Ìõ¼Ç¼ÖÐÓÐÈô¸É¸öÊôÐÔ£¬ÈôÆäÖÐijһ¸öÊôÐÔ×é(×¢ÒâÊÇ×é)ÄÜΨһ±êʶһÌõ¼Ç¼£¬¸ÃÊôÐÔ×é¾Í¿ÉÒÔ³ÉΪ...
ʲôÊÇÖ÷¼ü?ʲôÊÇÍâ¼ü?ËüÃÇÖ®¼äÓÐʲô¹Øϵ?
Íâ¼ü£ºÈôÓÐÁ½¸ö±íA£¬B£¬CÊÇAµÄÖ÷¼ü£¬¶øBÖÐÒ²ÓÐC×ֶΣ¬ÔòC¾ÍÊDZíBµÄÍâ¼ü£¬Íâ¼üÔ¼ÊøÖ÷ÒªÓÃÀ´Î¬»¤Á½¸ö±íÖ®¼äÊý¾ÝµÄÒ»ÖÂÐÔ¡£AΪ...
SQL server ÎÊÌâ,ʲôÊÇÍâ¼ü,ʲôÊÇÖ÷¼ü?Ò»¸ö±íµÄÍâ¼ü¿ÉÒÔ...
Íâ¼ü£ºÍâ¼ü (FK) ÊÇÓÃÓÚ½¨Á¢ºÍ¼ÓÇ¿Á½¸ö±íÊý¾ÝÖ®¼äµÄÁ´½ÓµÄÒ»Áлò¶àÁС£Í¨¹ý½«±£´æ±íÖÐÖ÷¼üÖµµÄÒ»Áлò¶àÁÐÌí¼Óµ½ÁíÒ»¸ö±íÖУ¬...
mysqlÊý¾Ý¿â±íÖ÷¼üÓëÍâ¼üÔ¼Êø - °Ù¶È¾Ñé
mysqlÊý¾Ý¿â±íÖ÷¼üÓëÍâ¼üÔ¼Êø ·½·¨/²½Öè 1 1.ÔÚ´´½¨±íµÄʱºò¿ÉÒÔΪ±íÖÐij¸ö×ֶδ´½¨Ö÷¼ü£¬Ö÷¼üµÄ×÷ÓÃ...
ÇëÎÊÊý¾Ý¿âÖеÄÖ÷¼üºÍÍâ¼üÊÇʲôÒâ˼?
key£©£ºÒ²³ÆΪÖ÷Âë»òÖ÷¹Ø¼ü×Ö£¬ÓÃÓÚΩһµØÈ·¶¨Ò»¸öÔª×éµÄÊôÐÔ»òÊôÐÔ×é(¸´ºÏÖ÷Âë)¡£Ã¿¸ö¹Øϵ¶¼ÓÐÒ»¸ö²¢ÇÒÖ»ÓÐÒ»¸öÖ÷Âë¡£Íâ¼ü£¨...