mysqlÖÐINSTRº¯ÊýµÄÓ÷¨
mysqlÖÐINSTRº¯ÊýµÄÓ÷¨
INSTR(×Ö¶ÎÃû, ×Ö·û´®)
Õâ¸öº¯Êý·µ»Ø×Ö·û´®ÔÚijһ¸ö×ֶεÄÄÚÈÝÖеÄλÖÃ, ûÓÐÕÒµ½×Ö·û´®·µ»Ø0£¬·ñÔò·µ»ØÎ»Ö㨴Ó1¿ªÊ¼£©
SELECT * from tblTopic ORDER BY INSTR( topicTitle, 'ha' ) > 0 DESC
SELECT INSTR( topicTitle, 'ha' ) from tblTopic
mysqlÖÐʹÓÃinstrÅäºÏINÅÅÐò
½«instr½á¹û×÷ΪһÁУ¬°´ÆäÅÅÐò
select id,1 from world_guide where id = 32
union
select * from
(select id, instr('30,35,31,',id+',') as d from
world_blog where id in (30,35,31) order by d) as t;
Êä³ö
+----+---+
| id | 1 |
+----+---+
| 32 | 1 |
| 30 | 1 |
| 35 | 4 |
| 31 | 7 |
+----+---+
4 rows in set, 6 warnings (0.02 sec)
±íA
×Ö¶Î:ÐÕÃû name
ÕÅÈý
ÍõÎå
±íB
×Ö¶Î:±êÌâ title
ÐÅÏ¢Ò» ÕÅÈý·¢²¼
ÐÅÏ¢¶þ ÍõÎå·¢²¼
ÐÅÏ¢Èý ÕÅÈý·¢²¼
ÅÅÐаñ£¬°´±íAµÄÐÕÃû like %‘name’% Æ¥Åä ±íBµÄ title µÄÌõÊý½øÐÐÅÅÐò,
ÅÅÐаñÑùÀý
ÕÅÈý 2
ÍõÎå 1
select ÐÕÃû,count(b.title) from a inner join b on instr(b.title,a.ÐÕÃû)>0
group by ÐÕÃû
order by count(b.title)
select name,(select count(*) from ±íB where instr(title,±íA.name)
from ±íA
order by 2 desc
Ïà¹ØÎĵµ£º
ÏȰ´ÕÕÏÂÃæµÄ±í½á¹¹´´½¨mysql_order_by_testÊý¾Ý±í£¬ÎÒÃÇÓÃʵÀýÒ»µãÒ»µã¸æËßÄ㣬MySQL order byµÄÓ÷¨¡£
¡¡¡¡ORDER BY uid ASC
¡¡¡¡°´ÕÕuidÕýÐò²éѯÊý¾Ý£¬Ò²¾ÍÊǰ´ÕÕuid´ÓСµ½´óÅÅÁÐ
¡¡¡¡ORDER BY uid DESC
¡¡¡¡°´ÕÕuidÄæÐò²éѯÊý¾Ý£¬Ò²¾ÍÊǰ´ÕÕuid´Ó´óµ½Ð¡ÅÅÁÐ
¡¡¡¡ÎÒÃÇÀ´¿´
SELECT * from mysql_order_by_test OR ......
1£ºMysql ÃüÁî²»¿ÉÒÔÖ´ÐÐ
ÔÒò £ººÇºÇ ±ÈÈç show databases µÄÃüÁî £¬Ö´ÐÐÍêÖ®ºó ɶҲûÓÐ £¬×Ðϸ ÕÒÁËÔÒò £¬Oh my god ÉÙÁË ·ÖºÅ¡£
Ӧд³É£ºshow databases;
2£ºÃüÁîÐÐÖÐÎÄÂÒÂëÎÊÌâ
ÏÖÏó£ºmysqlµÄĬÈϱàÂëÉèÖÃΪutf-8£¬Ò³ÃæÒÔutf-8µÄ±àÂ뷽ʽдÈëµ½Êý¾Ý¿â¡£Óù¤¾ß²é¿´Ò»ÇÐÕý³££¬µ«´ÓmysqlµÄÃüÁîÐжÁÊý¾Ý³öÀ´× ......
MySQLµÄ×Ö·û¼¯Ö§³Ö(Character Set Support)ÓÐÁ½¸ö·½Ã棺
×Ö·û¼¯(Character set)ºÍÅÅÐò·½Ê½(Collation)¡£
¶ÔÓÚ×Ö·û¼¯µÄÖ§³Öϸ»¯µ½Ëĸö²ã´Î:
·þÎñÆ÷(server)£¬Êý¾Ý¿â(database)£¬Êý¾Ý±í(table)ºÍÁ¬½Ó(connection)¡£
1.MySQLĬÈÏ×Ö·û¼¯
MySQL¶ÔÓÚ×Ö·û¼¯µÄ ......