Initial Startup of MySQL Cluster
Starting the cluster is not very difficult after it has been configured. Each cluster node process must be started separately, and on the host where it resides. The management node should be started first, followed by the data nodes, and then finally by any SQL nodes:
On the management host, issue the following command from the system shell to start the management node process:
shell> ndb_mgmd -f /var/lib/mysql-cluster/config.ini
Note
ndb_mgmd
must be told where to find its configuration file, using the
-f
or
--config-file
option. (See
Section 4.4, “ndb_mgmd
— The MySQL Cluster Management Server Daemon”
, for details.)
For additional options which can be used with
ndb_mgmd
, seeSection 4.23, “Options Common to MySQL Cluster Programs”
.
On each of the data node hosts, run this command to start the
ndbd
process:
shell> ndbd
If you used RPM files to install MySQL on the cluster host where the SQL node is to reside, you can (and should) use the supplied startup script to start the MySQL server process on the SQL node.
If all has gone well, and the cluster has been set up correctly, the cluster should now be operational. You can test this by invoking the
ndb_mgm
management node client. The output should look like that shown here, although you might see some slight differences in the output depending upon the exact version of MySQL that you are using:
shell> ndb_mgm
-- NDB Cluster -- Management Client --
ndb_mgm> SHOW
Connected to Management Server at: localhost:1186
Cluster Configuration
---------------------
[ndbd(NDB)] 2 node(s)
id=2 @192.168.0.30 (Version: 5.1.41-ndb-6.3.31, Nodegroup: 0, Master)
id=3 @192.168.0.40 (Version: 5.1.41-ndb-6.3.31, Nodegroup: 0)
[ndb_mgmd(MGM)] 1 node(s)
id=1 @192.168.0.10 (Version: 5.1.41-ndb-6.3.31)
[mysqld(API)] 1 node(s)
id=4 @192.168.0.20 (Version:
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 ......
>>mysql:
1、查看所有表名:
show tables [from db_name];
2、查看字段信息
SHOW FULL COLUMNS from db_name.table_name
获取以下信息
Field :字段名
Type:字段类型
Collation:字符集 (mysql 5.0以上有)
Null :是否可以为NULL
Key:索引(PRI,unique,index)
Default:缺省值
Extra:额外(是否 aut ......
了解了一些最基本的操作命令后,我们再来学习如何创建一个数据库和数据库表。
1、使用SHOW语句找出在服务器上当前存在什么数据库:
mysql> SHOW DATABASES; +----------+
| Database | +----------+ | mysql |
| test | +----------+ 3 rows in set (0.00 sec)
2、创建一个数据库abccs
mysql> ......
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
......
For our four-node, four-host MySQL Cluster, it is necessary to
write four configuration files, one per node host.
Each data node or SQL node requires a
my.cnf
file that provides two pieces of
information: a connectstring
that tells
......