MySQL

I changed the int type of id to bigint. In fact, it may be better to change it back. An error may occur during database backup.This problem occurs during the testing of the developed website background system:Invalid Query: Duplicate entry '000000'

Later, after referring to the documents on the Internet, the MYSql database on the server was connected through Http. Record:First download the latest version of NaviCat from the NaviCat official website (www.NaviCat.com.cn ).After the installation

However, I am not going to describe the implementation details of a storage engine or the advantages and disadvantages of various storage engines. I just want to describe how mysql handles binlog and clarify several obfuscation problems.Binlog is

After ping and route, it is found that network communication is normal, and local connection discovery on the mysql machine is very fast, so the network problem is basically ruled out. I have encountered such a problem before, but I don't know how

It was originally used for installation. Therefore, when setting database usage (for example, 1), follow the official discuz suggestions, all selected are Non-Transactional Database Only (Only Non-transaction databases of MyISAM data engine are

MyISAM tables emphasize performance, and the execution speed is faster than that of InnoDB, but transactions are not supported. InnoDB provides advanced database functions such as external keys for transactions.MyIASM is a new version of the IASM

When installing mycheckpoint and assigning permissions to this monitored user, this secret is discovered:Copy codeThe Code is as follows:Mysql>Mysql> grant all privileges on mycheckpoint. * TO 'mycheckpoint _ user' @ 'localhost' identified by '123 ';

Internal issues related to the mysql databaseCause delete from table where col not in (select col from table group by xx)An error is reported.What we need to do isCopy codeThe Code is as follows:Create table tmp selete col from table group by

1. Mysql databases do not have an incremental backup mechanism. When the data volume is too large, backup is a big problem. Fortunately, the mysql database provides a master-slave backup mechanism, which is to write all the data of the master

Mysql> SELECT something FROM tbl_nameWHERE TO_DAYS (NOW ()-TO_DAYS (date_col) DAYOFWEEK (date)Returns the week index of date (1 = Sunday, 2 = Monday,... 7 = Saturday ). The index value complies with ODBC standards.Mysql> select dayofweek ('2017-02-03

1. Create primary key syntax Alter table table_name add constraint pk_name primary key (column name );2. Create foreign key syntaxAlter table news_info [subtable name] add constraint FK_news_info_news_type [CONSTRAINT name] foreign key (info_id)

First create a tableUse Test;Create Table TableTest ('Id' mediumint (8) default '0 ','Name' varchar (100) default'') TYPE = MyISAM;Import data to a data tableLoad Data InFile 'C:/Data.txt 'Into Table 'tabletest'Commonly used:Load Data InFile

Using MYSQL_PWD is insecure. See connection to MySQL server in MySQL 6.3."Mysql" uses the file named in the environment variable MYSQL_HISTFILE to save the command line history. The default value of the historical file is "$ HOME /. mysql_history ",

The following elements are involved in the insecure mysql service installed by default:I. Default mysql authorization tableIi. Lack of log capabilityIii. Password leakage for my. ini files4. Services are bound to all network interfaces by default.V.

1. digit type. The number types are classified into three types by my classification: integer, decimal, and number. My so-called "number classes" refer to DECIMAL and NUMERIC. They are of the same type. Strictly speaking, it is not a numeric type,

New or changed features:Security Enhancement: Enable strictly controlled positions from which user-defined functions can be loaded. The plugin_dir system variable hasBackported from MySQL 5.1. If the value is not empty, the User-Defined Function

Mysql Chinese sorting method 1Mysql is case-insensitive when querying strings. In programming mysql, The ISO-8859 character set is generally used as the default character set. Therefore, the case-sensitive conversion of Chinese encoding Characters

If you want to directly store binary data, such as image files and HTML files, in your MySQL database, this article is for you! I will show you how to store these files through HTML forms and how to access and use these files.Overview:. Create a new

Copy codeThe Code is as follows:Mysqldump-u user-p db tab1 tab2> db. SQL RestoreCopy codeThe Code is as follows:Mysql-u user-p db Refer:1. copy backup files: (ensure that the database has no write operations (you can lock the Table). Copying files

If you forget your MYSQL root Password, you can recover it through the following process.1. Send the kill command to the mysqld server to disable the mysqld server (not kill-9). The files that store the process ID are usually located in the