MySQL

Now there is a book table, which records the book information, the book ID is nh_id,Request to have a book chapter table, according to the chapter records the specific information of the book, foreign key nh_id corresponding to the Book table of the

Partition by scope, give each partition a certain range, the range must be contiguous and cannot be duplicated, use the values less than operator Let's start by creating a range partition tableCREATE TABLE employees ( id INT NOT NULL, fname

1. Mathematical FunctionsABS (X) absolute valueCeil (X) rounding upFloor (X) rounding downRandom number of RAND (X) 0-1ROUND (x) the nearest integer from XROUND (x, y) holds the decimal number of the X-bit and uses rounding when truncatedPOW (x, y)

First, IntroductionThe Query_event event records information in the form of text. When the Binlog format is statement, the executed statements are stored in Query_event, as follows:Mysql> Show Binlog events in "mysql-bin.000002"; +------------------+

In the My.ini file, change to:[Client]Default-character-set = UTF8port=3306[MySQL]Default-character-set=utf8[Mysqld]# The TCP/IP Port the MySQL Server would listen onport=3306# The default character set that would be used if a new schema or table is#

First, MySQL initial passwordThe newly installed MySQL default is no password, set the initial password can use the following life' New-password ' ' password '-s/data/3306/mysql.sock #socket多实例 After setting the initial password, you can

ERROR 1819 (HY000): Your password does not satisfy the current policy requirements,What if this problem arises?To enhance security, MySQL5.7 randomly generates a password for the root user, in error log, about the location of the error log and, if

1 Window System, MySQL data import exception2 analysis reason, mostly the character set is incorrect when importing and exporting3 specifying a specific character set when importing4 Case ListUse mysqldump to back up a database, and when using MySQL

#!/bin/bash#scripts SH batch_databasename.shBakfile=/data/dbbackupLogfile=/data/bak.logDbuser=xxxDbpasswd=xxxip=ifconfig | grep "inet addr"| grep Bcast| awk ‘{print $2}‘| awk -F":" ‘{print $2}‘nowtime=$ (Date +%y%m%d)#ser_port =cat

Character type#官网: https://dev.mysql.com/doc/refman/5.7/en/char.html#注意: The arguments in char and varchar brackets refer to the length of the character #char type: fixed length, simple rough, wasted space, fast access speed range of character

MySQL master-slave replication architecture and implementation of master-slave configuration 0, Master1-based, master2 from Node 1, the main node to open the binary log, ServerID[[email protected] ~]# vim

How to sort in MySQL:Select * from table name [where condition order by field name ( default is asc in ascending order )]ASC is in ascending order andDESC is used to specify descending orderOracle Neutron query:SELECT * from table name

SQL statement Format:· Add FOREIGN KEY constraint: ALTER TABLE from TABLE ADD constraint foreign key (shape: Fk_ from Table _ Main Table) foreign key (from Table foreign key field) references Main Table (primary key field);Note that the (') in the

CentOS7.4 installing MySQL pit recordtime:2018.3.19CentOS7.4 install MySQL online documents although many but not reliable also many, may because of the version and time of the problem, so record their own step on the pit process, if you find into

Querying data (single-table query)Query all columns select * from table name;Query the specified column Select field, field, field from table name;Add constant column when querying select ' New field ' as ' constant name ' from table name;Merge

Template data Downloadhttps://github.com/datacharmer/test_db1. Employees Database Installation(1) Employees Database IntroductionEmployees database for learning and testing, approx. 160M(1) Employees installationOfficial Document Installationhttps://

Check that the MySQL service has started and has startedThis command is not in the environment path.[Email protected] ~]# echo $PATH/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin[Email protected] ~]# export path=

I. Retrieval of data1.1. Retrieve a single column:SELECT prod_name from products;1.2. Retrieving multiple columns: SELECT prod_id, prod_name,prod_price from products;SELECT prod_id, Prod_name,prod_price from theproducts;1.3. Retrieve all

Install mysql5.6 and centos7mysql5.6 on CentOS7 There will always be some minor problems during MySQL installation, resulting in slow installation progress. add your own actual operations to Baidu search, summarize the installation methods, and make

MySQL Learning (1), MySQL Learning (I. MySQL Introduction Mysql is the most popular Relational Database Management System. In terms of WEB applications, MySQL is one of the best RDBMS (Relational Database Management System: Relational Database