MySQL Cluster Multi Computer Installation
Each MySQL Cluster host computer running an SQL node must have
installed on it a MySQL binary. For management nodes and data
nodes, it is not necessary to install the MySQL server binary, but
management nodes require the management server daemon
(ndb_mgmd
) and data nodes require the data node
daemon (ndbd
; in MySQL Cluster NDB 7.0 and
later, you can use ndbmtd
instead). It is also
a good idea to install the management client
(ndb_mgm
) on the management server host. This
section covers the steps necessary to install the correct binaries
for each type of Cluster node.
Sun Microsystems, Inc. provides precompiled binaries that support
Cluster. However, we also include information relating to
installing a MySQL Cluster after building MySQL from source. For
setting up a cluster using MySQL's binaries, the first step
in the installation process for each cluster host is to download
the latest MySQL Cluster NDB 6.2, MySQL Cluster NDB 6.3, or MySQL
Cluster NDB 7.0 binary archive
(mysql-cluster-gpl-6.2.19-linux-i686-glibc23.tar.gz
,
mysql-cluster-gpl-6.3.31-linux-i686-glibc23.tar.gz
,
or
mysql-cluster-gpl-7.0.11-linux-i686-glibc23.tar.gz
,
respectively) from the
MySQL Cluster downloads
area
. We assume that you have placed this file in each
machine's /var/tmp
directory. (If you do
require a custom binary, see
Installing from the Development Source Tree
.)
Data and SQL Node Installation — .tar.gz
Binary.
On each of the machines designated to host data or SQL nodes,
perform the following steps as the system
root
user:
Check your /etc/passwd
and
/etc/group
files (or use whatever
tools are provided by your operating
相关文档：
假设有表 tb1
ID ｜ name｜
----+--------+
1 ｜2toon｜
2 ｜1*xyz｜
语句1：
select * from tb1 where ID='2toon' or name ='2toon';
mysql服务器在某模式下，可以执行这条句，就成功返回两条记录，原因在于 ID=‘2toon’ 加了单引号，mysql解释为 ID=2.
语句2
select * fro ......
这次是Fotolog
的经验，传说中比Flickr更大的网站
，Fotolog在21台服务
器上部署了51个memcached实例，总计有254G缓存空间
可用，缓存了多达175G的内容，这个数量比很多网站的数据库都要大的多，原文是A Bunch of Great Strategies for Using Memcached and MySQL Better Together
，我这里还是选择性的翻译以及按照 ......
里是一个使用日期函数的例子。下面的查询选择了所有记录，其date_col的值是在最后30天以内：
mysql> SELECT something from table
WHERE TO_DAYS(NOW()) - TO_DAYS(date_col) <= 30;
select TO_DAYS(NOW());
select now() ;
DAYOFWEEK( ......
首先要声明一点，大部分情况下，修改MySQL是需要有mysql里的root权限的，
所以一般用户无法更改密码，除非请求管理员。
方法一
使用phpmyadmin，这是最简单的了，修改mysql库的user表，
不过别忘了使用PASSWORD函数。
方法二
使用mysqladmin，这是前面声明的一个特例。
mysqladmin -u root -p password mypas ......
create procedure all_joiner_message( in captions varchar(255), in contents text, in objectid int, in types int , out count int)
begin
declare userids int;
DECLARE _done IN ......
