¸Õ¿ªÊ¼Ñ§Ï°Ê¹ÓÃGDBµ÷ÊÔ¹¤¾ß£¬°´ÕÕÊéÉϵķ½·¨µ÷ÊÔÄںˣ¬ÔÚU-BootÉÏÉèÖÃÃüÁîÐвÎÊý¡¢Æô¶¯Äںˡ£
u-boot> set bootargs noinitrd root=/dev/mtdblock 2 console=kgdb kgdbwait
u-boot> tftp 0x30000000 uImage.img (ÏÂÔØÍê±Ï)
u-boot> bootm 0x30000000
Æô¶¯ÐÅÏ¢ÈçÏ£º
S ......
±íA£º
²¿ÃűàºÅ ²¿ÃÅÃû³Æ
DepartID varchar£¨100£© DepartName varchar£¨50£©
A ×î¸ß¼¶Ö÷¹Ü²¿ÃÅ
A01 ÈËÁ¦×ÊÔ´²¿
A02 ²ÆÎñ²¿
A03 ÖÆÔ첿
A0 ......
order±íÖÐÓÐ orderId status
Çó¸ù¾Ýstatus·Ö×é ²¢Çó³öÿ×éorderIdµÄÊýÁ¿
ÐÂÊÖ Çë¸ßÊÖÖ¸½Ì
SQL code:
select count(orderId) from Tanname group by status
SQL code:
select count(1) as ÊýÁ¿,status
from order
group by status
SQL code:
********************************************** ......
ÓÐÒÔÏÂÊý¾Ý±í
index n
1 100
2 200
3 300
4 400
5 500
..
9 900
µ±ÎÒÐèÒª 2 ÌõÊý¾ÝÇÒ×ÜÊýºÍΪ800µÄʱºò½á¹ûΪ
3 300
5 500
µ±ÎÒÐèÒª 3 ÌõÊý¾ÝÇÒ×ÜÊýºÍΪ800µÄʱºò½ ......
A±íÄÚÈÝBÁдó¸ÅÈçÏÂ:
1234567
1234
1abc234
123ab45
1234
Ïë²éѯµÄʱºòBÁгÉΪ
1,2,3,4,5
1,2,3,4
1a;1b;1c;1d,2,3,4
1,2,3a;3b,4
1,2,3,4
µÄЧ¹û¿ÉÒÔÂð,ллÁË!!!
¼´°ÑÊý×ÖÓöººÅ¸ô¿ªÁË,×ÖĸҪ¼ÓÇ°ÃæµÄÊý×ÖÓ÷ֺŸô¿ª,×ÖĸºóÃæÈç¹ûΪÊý×Ö,ÔòºóÃæÎª¶ººÅ.
°ï¶¥ ÓÐÄѶÈ
ÏÈÕ ......
Çë½ÌÒ»¸öÎÊÌâ
±í a ÈçÏ ҪÓÃÒ»ÌõÓï¾ä
Òª²é³öÕâÑùµÄ
name score paiming
aa 90 1
bb 80 2
cc 70 3
create table a
(name char(2) not null,
score int not null
)
insert into ......