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

Çë½Ì¸÷λ´ó¸çÒ»¸öSqlÎÊÌ⣬Äĸö°à¼¶µÄ½Ìʦ´ýÓö×î¸ß£¿

СµÜ×î½üÓöµ½Ò»¸öÎÊÌ⣬ҪÇóµÃ³öÄĸö°à¼¶µÄ½Ìʦ´ýÓö×î¸ß£¬°Ñͬһ¸ö°à¼¶µÄ½Ìʦ´ýÓöºÏ¼ÆÆðÀ´


°à¼¶±í                  ½Ìʦ±í

°à¼¶ID                ½ÌʦID
°à¼¶Ãû×Ö              °à¼¶ID
                      ½Ìʦ´ýÓö 


Ê×ÏÈÏëµ½µÄÊÇÓÃMAX£¨´ýÓö£©,µ«ÊÇÖ»Äܵóö´ýÓö×î¸ßµÄ½Ìʦ£¬ºóÏëһϣ¬ºÃÏñÖ»Óд洢¹ý³Ì²ÅÄÜ´¦Àí£¬¶øÇÒ´æ´¢¹ý³ÌÖл¹ÒªÑ­»·´¦Àí°à¼¶ÊýºÍ½ÌʦÊý£¬±È½ÏÂé·³¡£

×îºóÒªÇó°´ÕÕ´ýÓö×î¸ßµÄ°à¼¶ÅÅÐòÏÂÀ´¡£

²»ÖªµÀ¸÷λ´ó¸çÓÐûÓкõÄ˼·ºÍ·½·¨£¬×îºÃµÄÊÇÒ»¾äSql¾ÍÄÜÍê³ÉµÄ¡£ÈçÓдúÂë¸üºÃ£¬Ð»Ð»ÁË



select °à¼¶ID,sum(½Ìʦ´ýÓö)
from ½Ìʦ±í
group by °à¼¶ID
order by 2 desc

SQL code:
select °à¼¶Ãû×Ö,sum(½Ìʦ´ýÓö)
from ½Ìʦ±í ,°à¼¶±í
where ½Ìʦ±í.°à¼¶ID = °à¼¶±í.°à¼¶ID
group by °à¼¶Ãû×Ö
order by 2 desc


SQL code:
select m.* , avg(n.½Ìʦ´ýÓö) ½Ìʦ´ýÓö from °à¼¶±í m , ½Ìʦ±í n where m.°à¼¶ID = n.°à¼¶ID group by m.°à¼¶ID,°à¼¶Ãû×Ö order by ½Ìʦ´ýÓö desc


ÊÇÓÃavg°É?ƽ¾ù´ýÓö°É?

²»ÊÇÓÃsum.

SQL code
{


Ïà¹ØÎÊ´ð£º

ÇóSQL£¿

´ó¼ÒºÃ£¬ÇëÎÊÔÚ±íMÖÐÓÐ×ֶΣºa b c d e 
ÎÒÏë²é³öÆäÖÐÂú×ãÏÂÃæÈÎÒâÒ»ÏîµÄÊý¾Ý£¬1.×Ö¶Îa µÄÖµ²»ÊÇ ¡®Êé»ò±Ê»ò±¾¡¯ÖÐÈÎÒ»£¬2.aΪÊéµÄʱºò×Ö¶Îb,cÊÇ¿Õ;3.µ±aֵΪ±ÊµÄʱºòdÊÇ¿Õ;4.µ±aΪ±¾µÄʱºòb,d,e¶¼ÊÇ¿Õ;5.È ......

¹ØÓÚgroup byµÄsqlÓï¾ä£¿

  with adod_dict do
    begin
    close;
    commandtext:='select bgqxcode,count(*) wjsl from wscl_wsda_file where wjnd=:tnd group by bgqxcode'; ......

sql ÎÊÌâ

PBÖпª·¢µÄ¡£

DateTime startTime=DateTime(em_1.Text)
DateTime endTime=DateTime(em_2.Text)

string sql
sql = dw_1.GetSQLSelect()+"Where (StartTime> '"+startTime+&q ......

sql ²éѯ

  ÎÒÓÐÒ»¸öÔºÍÈÕ×é³ÉµÄÊý×Ö£¬ÓÐÁ½×éÔºÍÈÕ
ÏëÔÚÉí·ÝÖ¤ºÅÖÐÌôÑ¡³öÔڸøÃÁ½×éÔÂÈÕÖ®¼ä³öÉúµÄÈË£¬²»ÖªµÀÓ¦¸ÃÔõôд.
Éí·ÝÖ¤ºÅÓпÉÄÜÊÇ15λ»òÕß18λ

ÔÂÈÕ×éºÏµÄÐÎʽÈçÏÂ
10-17/04-20
ÔÂ-ÈÕ/ÔÂ- ......

SQL 2008 ÐÂÊÖÎÊÌ⣿£¿£¿

sql 2008ÖÐР¸½¼ÓµÄÊý¾Ý¿â£¬ÈçºÎÓÃDDLÓïÑÔÌí¼Ó¡°ËùÓÐÕß¡±£»
ÊÖ¶¯µÄ·½Ê½Îª£ºÊó±êÔÚи½¼ÓµÄÊý¾Ý¿âÉÏÓÒ¼ü——>ÊôÐÔ——>Îļþ——>ËùÓÐÕߣ¬È»ºóÓұ߿հ׼üÑ¡Ôñ£»
DDLÓï¾ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ