MySQL

Log in to MySQLmysql-h192.168.56.1 -p33060-uroot-pEnter Password: * * * *1. Add UsersInsert into MySQL. User (Host,uservalues('%''xiaoming'), Password ('xiaoming123'));You can now log in to MySQL using your account (xiaoming,xiaoming123). But only

mysql-Learning -9-20170524-Copying principleAnalyze the characteristics of replication thread mysql5.7 replicationThe main library writes the log binlog process,InnoDB to redo and commit can think of this transaction complete INODB Redo prepare (no

1. Use table aliasesBenefits:A, shorten the SQL statement.B, allow the same table to be used more than once in a single SELECT statement.Input:SELECT Cust_name,cust_contactFrom customers as c,orders as o,orderitems as IOWHERE c.cust_id =

Java calls MySQL instance:Package com.tanglei.test1;Import java.sql.*;public class testsql{public static void Main (String []args) {MySQL mysql=new MySQL ();}}Class mysql{MySQL jdbc url writing method: jdbc:mysql://host Name: The name of the

MySQL master-slave replication principle in-depth analysis and practiceMySQL master-slave copy Drawing description:650) this.width=650; "Src=" https://s2.51cto.com/wyfs02/M02/96/AB/wKiom1kkLyrSi5E7AAB_mfYhi7g870.png-wh_500x0-wm_ 3-wmp_4-s_1035712814.

Reference Document: http://www.178linux.com/60625Node OneModify configuration file Settings unique ID open binary log[[email protected] ~]# VIM/ETC/MY.CNF Add the following [mysqld] log-bin=master_bin open binary log server_id=1 to the primary node

When mysql/mariadb across the internet for replication, others can steal mysql/mariadb copy information, which is clear text, so there is no security, where the copied information through SSL encryption1. Create a certificate centerCreate a

(1) + : addition Operation (2) -: subtraction operation *: multiplication operation (4) /: division operation, return quotient (5) %: redundancy operation, return remainder Mysql> CREATE TABLE tmp14 (num INT);Mysql> INSERT into

One: MYSQL (https://dev.mysql.com/downloads/mysql/), automatic identification operating system provides optional download packageII: Downloads After the prompt registration, "No thanks,just start my download" direct download three: After

MySQL table operations 1,//create tables mysql>create table usertest (id int () PRIMARY key NOT NULL Auto_increment,url varchar (a) not null); 2 Change table name mysql>alter  table usertest Rename to Cmf_usertest;mysql>alter table zm_useroplog  day 

The date and time type of MySQL: Divided into times, date, DateTime, timestamp, year, mainly summarizes the use of the following years:1. Type support: Year with year (4), note that no year (2) is defined, otherwise the error "[ERR] 1818-supports

For the following table,1. Scenario: Query the teacher's information for the maximum number of days to substitute.Method One: Select% from teacher order BY day DESC LIMIT 1;There is a loophole in this approach: the teacher with the most days of

MySQL is MyISAM by default. MyISAM does not support transactions, while InnoDB supports. InnoDB autocommit By default is open, that is, each SQL statement will be encapsulated into a transaction by default, automatically commit, which will affect

The previous article describes database lookup filtering using some keywords with corresponding SQL statements, but the complexity of the WHERE clause itself increases as the complexity of filtering conditions increases. We can then use regular

The duplicate data method in the mysql query table. INSERT INTO hk_test(username, passwd) VALUES('qmf1', 'qmf1'),('qmf2', 'qmf11') delete from hk_test where username='qmf1' and passwd='qmf1' Duplicate data records in the query table in MySQL: View

MYSQL is a question that uses character functions to filter data. mysql characters Problem description: Structure: Test has two fields,Col1 and col2 are both character fields,The contents in the table are all three numbers separated by commas (,)

Mysql calculates the record whose two or more fields are NULL, and mysqlnull Core code /* ------------------------------ Calculate the records t1: id, id1, id2, id3, id4, id5, and id6 with two or more NULL fields. The field id is the primary key;

Check the installation information of mysql on the linux server. View mysql installation information: # Ps-ef | grep mysql Usr/bin/mysql indicates the mysql running path.Var/lib/mysql refers to the storage path of mysql database

Check the tables that use the shared tablespace and the shared tablespace.Check tables that use the shared tablespace   Recently I took over a new database machine and found that some tables in some databases do not have ibd files but frm files,

Mysql-connector-java corresponds to mysql version, mysqlconnectorjava Record the ing between mysql-connector-java and mysql versions. For more information, see the latest version, Time: January 1, May 23, 2017 Official Website document