MySQL

Under Win7 by decompression installation MySQL 5.7 has been the start of the unsuccessful, the online search for a long time finally found a solution, record:1. Unzip the downloaded compressed package2, in the decompression directory, the My-default.

|  All | Full table Scan|  Index | Index full scan|  Range | Index range scanning, common language =,between and other operations|  Ref | Use a non-unique index scan or a unique index prefix scan to return a single record that often appears in an

description Under construction statement, the meaning of the following two parameters:　The first parameter specifies the type of ResultSet. The options are:type_forward_only: Default type. Only forward access is allowed and is not affected by

Add some of the things that are constrained in the previous chapter. We recommend the "constraint abbreviation _ field name" When setting the name of the constraint, which makes the person look clear. For example: Fk_deptno, we can probably know by

An unreasonable design of an index or lack of an index can create obstacles to the performance of the database and the application. Efficient indexing is important for good performance. The design index is that the guidelines should be considered:(1)

Import and Export dataTurn the table into SQL codeBackup and restoreincrease, delete, change, check CRUDAdd to:INSERT into [(column 1, column 2 ...)] VALUES ([, ' Value 2 '))Attention:1. Columns and values to match (quantity, type, order)2. The

Public interface Daointer {/** number of data bars displayed on a page */Public final Integer numforonepage=5;/*** Query operations on the database** @param sql* A SQL statement used by PreparedStatement* @param objects* Array of conditions matching

Requirements: Detect MYSLQ from the library status, skip fixed error number, detect every 30 seconds, if eligible to automatically skip or restart from library 1) remove MySQL from the library keyword [[email protected] scripts]# mysql-u root-

1. Simple querySELECT * from info;Select Code as ' Code ', name as ' name ' from info;2. Conditional querySELECT * from car where code = ' c002 ';SELECT * FROM car where brand = ' b001 ' and power = 130; #或用or3. Fuzzy querySELECT * from car where

In development, we know that the bottleneck of most applications is the execution time of SQL statements, where the security of SQL statements is not discussed, only high-performance SQL statements are discussed, and the legendary----index is

Mysqldump () {echo  "start   $mysql _dbname1  $mysql _dbname2  backup ..." if [ -d  "${backdir" }/${date} " ];thenecho " Mysql database dir already exists. " exit 1elsemkdir -p ${backdir}/${date}echo  "Start Backup  ${mysql_dbname1}  ..."/usr/bin/

importjava.sql.DriverManager;importjava.sql.ResultSet;importjava.sql.SQLException;importjava.sql.Connection;importjava.sql.Statement;publicclassMysqlDemo {    publicstaticvoidmain(String[] args) throwsException {        Connection conn = null;       

Rationalization of table design (follow 3NF) 1NF: Table columns are atomic, non-decomposed (column information cannot be decomposed, as long as the relational database automatically satisfies 1NF) 2NF: The records in the table

Learning something must be done by oneself to try to know if it is true. Always want to practice node's use, there is no good idea, after the classmate reminded, found that I can actually use node to write a blog. I have a lot of work to do with the

A slow query needs to be logged and a configuration file with a slow query is added./etc/my.cnfGeneral_log=offLog_output=tableSlow_query_log=1long_query_time=0.3 General_log=off will log all queries and suggest close (set global general_log

It took me two nights to study MySQL's beginner application and record it here.1. Installation under Windows systemI use the WIN10 system, in http://dev.mysql.com/downloads/mysql/download the corresponding version of MySQL, downloaded after the

Yum List | grep MySQLYum install-y mysql-server MySQL mysql-develService mysqld StartMysqladmin-u root password ' root '//Use this command to set the root account password to rootAt this point we can log in to our MySQL database via the mysql-u root-

Flush tables with read lock, flushtables Recently, mysql used locks in master-slave replication. Reference: http://blog.csdn.net/arkblue/article/details/27376991 1. FLUSH TABLES WITH READ LOCK This command is global read lock. After the command is

Reset the root password for mysql and set the root password for mysql. Recently, mysql was used in another project. Since mysql was installed a long time ago, the root password was forgotten. Windows: 1. log in as a system administrator; 2. Stop the

Mysql installation and startup tutorial (two methods), mysql two methods Mysql installation and startup: Method 1 (simple version ): Method 2: 1. Run cmd to enter the mysql installation directory bin, for example, D: \ MySQL Server 5.6 \ bin.