MySQL

Synchronize Database Automation scripts #! /Bin/sh www.2cto.com read-p "Please keyin your ssh host:"-t 30 host_ipread-p "Please keyin your ssh user: "-t 30 usernameread-p" Please keyin your ssh pass: "-t 30 passwordread-p" Please keyin your sync

30 methods for optimizing SQL statement query in mysql: 1. to optimize the query, try to avoid full table scanning. First, create an index on the columns involved in where and order. 2. Try to avoid using it in the where clause! = Or <> operator.

When upgrading the database using the synchronization tool and Common commands between data of different mysql versions, you usually need to synchronize the data in the old version to the new version of mysql service. For the MyISAM format, you can

Why does MySQL table correspond to only one. frm file, no. MYD and. the MYI file learned MySQL today and found that when creating a new database table, the table only corresponds to one. frm file, but no. MYD and. MYI file. After some searching, I

MySQL Statement Review show databases; // display all databases select database (); // view the current database show tables; // display the Table Name USER db_name [;] // switch database desc tb_name; /DESCRIBE city;/EXPLAIN city; // display

Solve the problem that the virtual machine linux mysql database could not be remotely accessed the day before yesterday, boring to install a mysql on the CentOS in the virtual machine, and suddenly wanted to use jdbc connection to operate the

SQL statement for mysql time operations select * from mytest where (select DATEDIFF (now (), current) = 0); // SELECT OrderId, DATE_ADD (OrderDate, INTERVAL 2 DAY) AS OrderPayDateFROM Orders add 2 days to "OrderDate" and the result is 16:25:46. 635

MySQL InnoDB manages and backs up binary logs (I) Importance of binary logs if there is data backup at a certain point in time and all binary logs since then can replay the binary logs since the last full backup and" roll back "all changes (ii)

Mysql: Communications link failure solves the problem of using Connector/J to connect to the MySQL database. After the program runs for a long time, the following error will be reported: Communications link failure, the last packet successfully

When you install or use MYSQL, you will find that there is an information_schema database besides the database you have installed. What is the use of the information_schema database? If you use a WordPress blog, you may wonder if you want to install

MYSQL sharing: Obtain the complete Definition Statement of the access process [SQL] SELECT db, specific_name AS OBJECT_NAME, CONCAT (CHAR (13), CHAR (10), 'delimiter $ ', CHAR (13), CHAR (10), CHAR (13), CHAR (10), 'use', db, ''$ ', CHAR (13 ), CHAR

The master/slave replication interruption caused by mysql_upgrade solves the problem of processing the 1548-Cannot loadfrom mysql on the master server in the production environment. proc. the table is probably successfully upted, and an alarm is

In many cases, mysql only requires local connection, that is, local connection (the server itself). This is also the case by default, and remote connection is not supported by default.But sometimes, when we need to separate mysql from a host or

The procedure for recording a MySQL logical backup and recovery drill is roughly as follows: get data from 42.121.189.236 to 192.168.1.119 and then send the data to 192.168.1.110 for recovery. Next, let's take a look at this process. (1) get data

MySQL hardware acceleration: the Flash storage technology contributes the most to the database bottleneck. I am afraid I/O is the best choice. I/O optimization theories on the market and on the network are all about I/O. With the hardware technology

Mysql database/table sharding is a good way to distribute database pressure. Table sharding refers to dividing a table structure into multiple tables, which can be stored in the same database or in different databases. Of course, you must first know

Mysql create table: The call path of the Cpp Code create table is as follows (5.1.58): do_command (SQL _parse.cc)-> dispatch_command (SQL _parse.cc)-> mysql_parse (SQL _parse.cc) -> mysql_execute_command (SQL _parse.cc)-> mysql_create_table (SQL

Install and use RMySQL in Windows. first install R,: http://ftp.ctex.org/mirrors/CRAN/bin/windows/base/ 2. install R-tools, http://ftp.ctex.org/mirrors/CRAN/bin/windows/Rtools/ 3. install MySQL (I installed MySQL 5.5. in the R installation directory,

Mysql table is marked as crashed and last (automatic ?) Repair failed solution 1. my colleague's server reported an error when backing up mysqldump. This is because the myisam table has too much data. At some point in time, the MyISAM table that

MySQL Data File description 1. mySQL Data File description first read MySQL DataDirectory file: dave here, mysql is our database name, we are viewing the mysql database: in MySQL, each database has a folder named after the database in the defined