1 check whether mysql service is installed by default in the system. If so, uninstall it. 1) Check command
rpm -qa|grep mysql
2) Uninstall command
rpm -e --nodeps mysql-libs-5.1.73-7.el6.x86_64
2 if it is CentOS 7, a mysql branch database mariadb will be installed by default. You must uninstall this database first 1) Search
rpm -e --node ...
Posted by newbie5050 on Thu, 05 May 2022 10:21:04 +0300
GTID realizes master-slave replication data synchronization
GTID is a successfully executed global transaction ID generated based on the original mysql server. It consists of server ID and transaction ID. this global transaction ID is unique not only on the original server, but also on all mysql servers with master-slave relationship. Officiall ...
Posted by dharprog on Thu, 05 May 2022 06:29:39 +0300
The system has been in operation for many years. The database server has also been running for many years, and its performance is relatively old. The capacity of the SSD hard disk is only 250G. Under various demands, the disk of the current server is about to be insufficient. Therefore, the migration of this database was started.
Database and table building
view the database
-- View all databases
[take mine as an example, the following are]
mysql> show databases; ±-------------------+ | Database | ±-------------------+ | information_schema | | mysql | | performance_schema | | sqlfortextbook | | studb | | sys | ±------------- ...
After learning from the previous article, we know that binlog will record all executed DDL and DML statements in the database (except data query statements select, show, etc.). Note that the operations of all libraries are recorded by default, so if we have alternative requirements, such as only allowing a certain library to record b ...
Posted by work_it_work on Tue, 03 May 2022 21:58:30 +0300
2. Operation database
2.1 operation database
2.2 column type of database
tinyint very small data 1 bytesmallint smaller data 2 bytesmediumint medium size 3 bytesint standard integer 4 bytesbigint larger datafloat floating point number 4 bytesdouble floating point number 8 bytesFinancial calculation of floating point num ...
Posted by grumpy on Tue, 03 May 2022 19:40:00 +0300
This article mainly contains the advanced part of the 72 questions in the SQL article, which is a must-tested question in the interview. It mainly includes the more difficult level (18 questions) and the difficult level (4 questions). The questions are more complicated, and my answer may not be the best solution. , Welcome everyone to correct m ...
Posted by glcarlstrom on Mon, 02 May 2022 21:55:06 +0300
1, Introduction to mycat
MyCat is an open source distributed database system. It is a server that implements MySQL protocol. Front end users can regard it as a database agent and access it with MySQL client tools and command line. Its back end can communicate with multiple MySQL servers with MySQL native protocol or with most mainstream databas ...
Posted by versatilewt on Mon, 02 May 2022 19:49:08 +0300
1, What is JDBC
When it comes to JDBC, we should first think of the 13 specifications in Java. One of them is JDBC. What is it and what is its use?
Let's take a look at Baidu Encyclopedia first
In short, it is the method of connecting the database with Java, but we all know that the Java language is developed and maintained by Oracle company, ...
Create test library
Create the database and set the encoding to utf8
create database zabbix character set utf8 collate utf8_bin;
Create user and set password
create user 'zabbix'@'localhost' identified by '<password>';
to grant authorization
Let zabbix users have all permissions of zabbix Library (local)
grant all pr ...
Posted by goldfiles on Mon, 02 May 2022 09:19:53 +0300