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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 ID=concat(ID,'ABC');
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package com.google.i_sales.service.data;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.uti ......
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
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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 > ......
To support MySQL Cluster, you will need to update
my.cnf
as shown in the following example.
You may also specify these parameters on the command line when
invoking the executables.
Note
The options shown here should not be confused with thos ......
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