尊龙凯时人生就是博

sqlÖÐʵÏÖÊý¾Ý¼ìË÷µÄÓï¾äÊÇ

sql ÓÃÓÚÊý¾Ý¼ìË÷µÄÓï¾äΪ select¡£Óï·¨°üÀ¨ select£¨Ö¸¶¨ÁУ©¡¢from£¨Ö¸¶¨±í£©¡¢where£¨Ö¸¶¨Ìõ¼þ£©¡£Ê¾Àý°üÀ¨¼ìË÷ËùÓÐѧÉúÐÕÃûºÍÄêËê¡¢¼ìË÷ÄêËê´óÓÚ 18 ËêµÄѧÉú¡¢¼ìË÷Ìض¨Ñ§ÉúµÄËùÓÐÐÅÏ¢¡£

SQL ÖÐÊý¾Ý¼ìË÷Óï¾ä

SQL ÖÐÓÃÓÚ¼ìË÷Êý¾ÝµÄÓï¾äÊÇ SELECT¡£

Óï·¨£º

SELECT 
     
FROM 
    
WHERE 
    

µÇ¼ºó¸´ÖÆ

×é¼þ£º

SELECT£ºÖ¸¶¨Òª¼ìË÷µÄÁС£¿ÉÒÔʹÓÃÐǺŠ(*) ÌåÏÖÑ¡ÔñËùÓÐÁС£

FROM£ºÖ¸¶¨Òª´ÓÄĸö±íÖмìË÷Êý¾Ý¡£

WHERE£ºÖ¸¶¨¼ìË÷Ìõ¼þ£¬ÓÃÓÚ¹ýÂ˳öÇкÏÌõ¼þµÄÐС£

ʾÀý£º

¼ìË÷ѧÉú±íÖÐËùÓÐѧÉúµÄÐÕÃûºÍÄêË꣺

SELECT 
    name, 
    age 
FROM 
    students

µÇ¼ºó¸´ÖÆ

¼ìË÷ÄêËê´óÓÚ 18 ËêµÄѧÉú£º

SELECT 
    name, 
    age 
FROM 
    students
WHERE 
    age > 18

µÇ¼ºó¸´ÖÆ

¼ìË÷Ìض¨Ñ§ÉúµÄËùÓÐÐÅÏ¢£º

SELECT 
    * 
FROM 
    students
WHERE 
    name = "John Doe"

µÇ¼ºó¸´ÖÆ

ÒÔÉϾÍÊÇsqlÖÐʵÏÖÊý¾Ý¼ìË÷µÄÓï¾äÊǵÄÏêϸÄÚÈÝ£¬¸ü¶àÇë¹Ø×¢±¾ÍøÄÚÆäËüÏà¹ØÎÄÕ£¡

ÃâÔð˵Ã÷£ºÒÔÉÏչʾÄÚÈÝȪԴÓÚÏàÖúýÌå¡¢ÆóÒµ»ú¹¹¡¢ÍøÓÑÌṩ»òÍøÂçÍøÂçÕûÀí£¬°æȨÕùÒéÓë±¾Õ¾Î޹أ¬ÎÄÕÂÉæ¼°¿´·¨Óë¿´·¨²»´ú±í尊龙凯时人生就是博ÂËÓÍ»úÍø¹Ù·½Ì¬¶È£¬Çë¶ÁÕß½ö×ö²Î¿¼¡£±¾ÎĽӴýתÔØ£¬×ªÔØÇë˵Ã÷À´ÓÉ¡£ÈôÄúÒÔΪ±¾ÎÄÇÖÕ¼ÁËÄúµÄ°æȨÐÅÏ¢£¬»òÄú·¢Ã÷¸ÃÄÚÈÝÓÐÈκÎÉæ¼°ÓÐÎ¥¹«µÂ¡¢Ã°·¸Ö´·¨µÈÎ¥·¨ÐÅÏ¢£¬ÇëÄúÁ¬Ã¦ÁªÏµ尊龙凯时人生就是博ʵʱÐÞÕý»òɾ³ý¡£

Ïà¹ØÐÂÎÅ

ÁªÏµ尊龙凯时人生就是博

18523999891

¿É΢ÐÅÔÚÏß×Éѯ

ÊÂÇéʱ¼ä£ºÖÜÒ»ÖÁÖÜÎ壬9:30-18:30£¬½ÚãåÈÕÐÝÏ¢

QR code
sitemap¡¢ÍøÕ¾µØͼ