MySQL

1. Check the system status Check the status of the system by using some operating system tools, such as CPU, memory, swap, and disk utilization. Based on experience or compared with the normal status of the system, sometimes the system looks idle on

Next, let's talk about the hardware and Forum information of my servers,CPU: 2 quad-core Intel Xeon 2.00 GHzMemory: 4 GB DDRHard Disk: SCSI 146 GBForum: the number of online members is generally about 5000-the highest record is 13264.Next, based on

The following figure shows the data inserted into the tuangou table:Id web city type1. Beijing Food & Beverage2. Shanghai leisure and entertainment3% group Tianjin Food & Beverage4. Online Shopping in ShenzhenDiscount coupons for Shijiazhuang6%

MySQL supports several storage engines as processors for different table types. The MySQL storage engine includes the engine for processing transaction security tables and the engine for processing non-transaction security tables: ◆ MyISAM manages

When testing whether mysql is synchronized today, check the database and find that a MySQL Slave is not synchronized with the host. Check the Slave status:Mysql> show slave status \ GSlave_IO_Running: YesSlave_ SQL _Running: NoLast_errno.:

1. myisamchkTo use myisamchk, you must temporarily stop the MySQL server. For example, we want to repair the discuz database. Perform the following operations:# Service mysql stop (stop MySQL );# Myisamchk-r/absolute path of the database file/* MYI#

1. View Indexes(1) Unit: GBSelect concat (ROUND (SUM (index_length)/(1024*1024*1024), 2), 'gb') AS 'total Index size' FROM information_schema.TABLES WHERE table_schema LIKE 'database ';+ ------------------ +| Total Index Size |+ ------------------ +|

There are two methods available on the Internet: First:Uninstall the KB967723 patch.Log on to the server and go to control panel-add and delete programs-(check "show updates" at the top). You can see the updated KB967723 patch in it, and then

Method 1:Select 'name' from mysql. proc where db = 'your _ db_name 'and 'type' = 'Procedure' // Stored PROCEDURESelect 'name' from mysql. proc where db = 'your _ db_name 'and 'type' = 'function' // FUNCTIONMethod 2:Show procedure status; // Stored

G, the solution is as follows:In the/var/lib/mysql directory, delete ibdata1, ib_logfile1, and ib_logfile0, and restart MySql to recreate the above files:Mysqladmin-uroot-p shutdownSudo mysqld_safe &Done!The following are other articles on the

At the same time, the online access volume continues to increase. For servers with 1 GB of memory, the server even crashes every day or gets stuck from time to time. This problem has plagued me for using MySQL for more than half a month. scalable

1. The concat function is often used to convert Int to varchar. For example, the concat (8, '0') string '80' is obtained'2. Convert varchar into an Int string of the varchar type using cast (a as signed).Summary: type conversion is similar to SQL

Example:Copy codeThe Code is as follows:Create procedure 'justifygroupnum '()NOT DETERMINISTICSQL SECURITY DEFINERCOMMENT''BEGIN/* How to run: call justifyGroupNum ()*/DECLARE p_group_id int;Declare p_num int;Declare stopFlag int;DECLARE cursor_name

If you want to give a specific user access from all machines in a given domain (for example, mydomain.com ), you can issue a GRANT statement that uses the '%' wildcard character in the host part of the account name:If you want a specific user to

However, note that the following optimization is not complete. MYSQL has implemented many optimizations, but I don't have time to test them all.Some MySQL optimizations are listed below:Remove unnecessary parentheses:(A AND B) AND c OR (a AND B) AND

I. INSERT and REPLACEBoth INSERT and REPLACE statements INSERT new data into the table. The syntax of these two statements is similar. The main difference between them is how to process repeated data.1. General INSERT usage The INSERT statement in

I believe that many webmasters or independent Blog bloggers have the need to back up databases. Of course, there are many plug-ins that can help you complete this task in a rich Blog system such as WordPress. If you need to back up the database by

If you have hundreds of thousands of data records, you can search for some popular words, and then read the last few pages to repeat the old dream. Mysql is so tragic that it does not stop operating hard disks.Therefore, you can try to make mysql

1After installing MYSQL, change the ROOT password and useNet startmysqlI encountered this problem at startup.C: \ mysql \ bin \ mysqladmin-u root-p shutdownNet start mysql does not have this error prompt!*************2MySQL error 1067Q: I

I. data definition language)A document language is a language defined for the format and form of a document. It is the first thing that every database needs to create, the table relationships, column primary keys in the table, and the reference