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SELECT ROUND((SUM(getfeng)/SUM(totalfeng))*100) as feng from answerdata WHERE uid='151' AND targetid IS NOT NULL
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round£¨1.5£© =2
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grant all privileges on *.* to 'root'@'Ô¶³ÌµÇ½IP' identified by 'Ô¶³ÌµÇ½ÃÜÂë'
flush privileges;
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vi /etc/sysconfig/ipt ......
http://dev.mysql.com/doc/refman/5.1/zh/index.html
(MySql 5.1 ÖÐÎIJο¼ÊÖ²á)
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show databases; ÏÔʾÊý¾Ý¿â
drop database Êý¾Ý¿âÃû;ɾ³ýÊý¾Ý¿â
set names 'utf8';ÉèÖÃÊý¾Ý¿â±àÂëΪutf-8
source x:\Êý¾Ý¿âÃû.sql;µ¼È ......
Administration ¹ÜÀí
Kill a Thread ½áÊøÒ»¸öÏß³Ì
mysql > KILL 999;
Optimize Table ÓÅ»¯±í
mysql > OPTIMEZE TABLE foo;
Reload Users Permissions Ë¢ÐÂMySQLϵͳȨÏÞÏà¹Ø±í
mysql > FLUSH PRIVILEGES;
Repair Table ÐÞ¸´±í
mysql > ......
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mysql> select CONCAT('My', 'S', 'QL');
-> 'MySQL'
mysql> select CONCAT('My', NULL, 'QL');
-> NULL
mysql> select CONCAT(14.3);
-> '14.3'
È磺update test set ......
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mysql>create database test;
Query OK, 1 row affected (0.02 sec)
´´½¨Êý¾Ý¿â±í£º
mysql>use test;
Database changed
´´½¨Êý¾Ý¿â±í£º
myaql>create table user(SID VARCHAR(11), name VARCHAT(6) );
Query OK, 0 rows affected (0.08 sec)
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mysql>insert int use ......