MySQL

This article attempts to describe the optimal selection from the perspective of the schema and index created by the data table. Optimal Data Types The smaller the data, the better. Select the minimum data type that meets your needs. By saving

  1. Download Here:Http://dev.mysql.com/downloads/mysql/5.1.html SelectMysql-noinstall-5.1.xx-win32.zipDownload 2. decompress the package to a folder. 3. Install Change my-huge.ini Copy to c: \ windows and rename it my. ini In cmd(Run

Call the cursor.exe cutemany () function in the mysqldb Python library to complete batch processing. Today, this function is used to complete batch insertion.Routine:Def test_insertdb ():Conn = database. Connection (host = options. mysql_host,

When MySQL ServerWhen a Crash is damaged for unexpected reasons, you must perform disaster recovery. If you have regular database backup, disaster recovery should be much easier.The copied data can be restored, but this will still cause loss of some

SELECTCONCAT ('alter table', table_name, 'alter column', column_name, 'set default null; ') as col, TABLE_NAME, COLUMN_NAME, DATA_TYPEFROMINFORMATION_SCHEMA.columnsWHERETABLE_SCHEMA = 'test' -- represents the databaseANDData_type in ('varchar ',

The MySQL server adopts a modular style, and each part remains relatively independent, especially in the storage architecture. Storage EngineManage data storage and MySQL indexes. Through the defined API, the MySQL server can communicate with the

What command should I use to view the Mysql table structure? The following describes the commands for viewing the Mysql table structure in detail. If you have encountered a similar problem in the Mysql table organization, you may wish to take a look.

1. log on to the mysql monitor command: cmd>Mysql-u root-pThen press enter to enter the password 2. the mysql configuration file is my. ini under the installation directory. The slave database crashes directly, and the root user cannot log in.

User-friendly MySQL replace into usage (enhanced version of insert) When inserting data into a table, you often encounter this situation: 1. First, determine whether the data exists; 2. If the data does not exist, insert the data; 3. If the data

Query is the core of the database. The following describes how to implement Mysql multi-Table query. If you have encountered any problems in Mysql multi-Table query, take a look. Mysql multi-Table query: CREATE TABLE IF NOT EXISTS contact(  

I often encounter the need to export data from a database to an Excel file. Using some open-source class libraries, such as PHPExcel, is indeed easy to implement, but it does not support a lot of data, it is easy to reach the PHP memory usage limit.

Share a function written yesterday. The purpose is to find that the given time is the nth week of the month. [SQL] View plaincopy Delimiter $ Use't _ girl $ Drop function if exists 'weekofmonth' $ Create definer = 'root'

BlackHole: The black hole engine. Any data written will disappear and is used to record the relay storage of binlog replication! How to install: Use the configure command with the -- with-blackhole-storage-engine option when installing MySQL. The

Create procedure, Create function Below are their formats:Create proceduresp_Name ([proc_parameter])Routine_body Here, the parameter type can be in out inoutt, which means the same as the word, and IN indicates the passed parameter,"OUT" indicates

In MySQL, order by has two sorting methods: 1. Use ordered indexes to obtain ordered data 2. File Sorting When using explain to analyze and query,Use ordered indexes to obtain ordered data displayUsing index. File Sorting displayUsing filesort.1.

1. Optimize SQL 1) Use show status to learn the execution frequency of various SQL statements. Show status like 'com _ %'How many times Com_select and Com_insert are executed2) analyze inefficient SQL statements through Explain3) create an

Original article: http://lxh71105321.blog.163.com/blog/static/23988844200901394611940 /#   For a long time, I have been wondering why mysql Data insertion slows down when I use the MYISAM engine. I am puzzled Myisam does not support transactions.

The main solution is as follows: 1. mysql's authorized user permissions must be % instead of @ localhost 2. The connection characters used by jsp to connect to the database using the jdbc driver should be considered as remote access. 3. Remember: @ %

A few days ago, I encountered a strange problem in the management system. Today I have the opportunity to install the MySQL environment to reproduce this problem. Because it is not the most primitive environment, it may not be completely reproduced,

Reprinted from: http://hi.baidu.com/silvanote/blog/item/a5aab77996d458f90bd18748.html   To achieve this, the assql class library can perform some basic data operations even though the current version is not stable. Organize some of its instances and