MySQL

MySQL field encryption and decryption 1. Encryption: Aes_encrypt (' admin ', ' key ') decryption: aes_decrypt (password, ' key ') 2. Bi-directional encryption is encrypted by a key, which is only known when the key is decrypted. People to

First, download1.mysql Official website: https://downloads.mysql.com/archives/community/　　　　2. After the download is done, unzip　　　　3. Place your location and put the unpacked folder in your preferred locationSecond, configure

Workaround when the webpage has the above problem:Today, transfer the website between the two servers, and finally set the domain name interpretation to wait ... Then cmd to view the DNS interpretation situation: Explanation Success-Enter the

Http://blog.sina.com.cn/s/blog_499740cb0100ugs7.htmlThe above link is a classic explanation of why MySQL's MVCC partially solves the problem of Phantom reading.At the same time I need to understand that in business logic, transactions can be

When the UPDATE statement is executed, if the number of rows affected is 0, the returned is also true.$conn = new mysqli ();$sql = "Update ...";$query = $conn->query ($sql);Var_dump ($query); At this point, if the update SQL statement succeeds, but

The purpose of creating a unique index is not to increase access speed, but to avoid duplication of data. A unique index can have more than one but the value of the indexed column must be unique, and the value of the indexed column allows for a null

A period of time to learn Nodejs, try to build a small project, the use of the database, because almost no use, are looking for learning edge, naturally forget also fast, now enter to see, found to forget almost, can only re-query, good depressed,

PHP connection database is generally used in an object-oriented approach, you need to create an object, that is, build a Connection object, and then write the SQL statement, (add to delete), and finally execute the SQL statementWhere we used to

Reference: https://my.oschina.net/u/255939/blog/505598MySQL replication is a MySQL server (slave) that replicates logs from another MySQL server (master) and then parses the logs and applies them to itself, similar to data Guard in Oracle.MySQL

Solution One:1. Log in with root, modify/ETC/MY.CNF2. Add a line under [mysqld]: Lower_case_table_names=13. Restart the database toBecause MySQL is deployed on Linux, it is case sensitiveSolution Two:Check the database information for the project

　Because of the actual project involved, it is found that when the data volume of MySQL table reaches millions, the efficiency of normal SQL query decreases linearly, and the query speed is simply intolerable if the query condition in where is more.

1. Open and close the strict mode methodLocate the my.cnf(the Windows system is the My.ini) file in the MySQL installation directoryAdding strict_trans_tables in sql_mode means that strict mode is turned on, and if not joined, it means non-strict

1. Installation Environment: 1. vs2013 (vs development tools ) 2. mysql 5.7.10.0 ( installed mysql database version ) Https://dev.mysql.com/doc/connector-net/en/connector-net-versions.html http://dev.mysql.com/downloads/connector/net/ 3.

Comparison of the two modes:Statement Advantageslong history, mature technology;The resulting binlog file is small;The binlog contains all the database modification information, which can be used to audit the database security and so on.Binlog can

1., Spotlight on MySQLClient tools, with a beautiful UI interface, can monitor MySQL io, qcache, connections, buffer pool, etc., as well as the function of early warning2, Lepus[use more]　　An open source of domestic monitoring platform, can monitor

There are now two tables, table1 and Table2,table1 have 10 million data (ID primary key index), Table2 has three data (UID field 3,5,7);Select * from where inch Select from table2);A blink of an eye feels that the sentence should be quick; you

Mysql.connector Transaction Summary:Connection.autocommit = 0 (default value)Transaction processingUsing the Connection.commit () method#!/usr/bin/env python#-*-coding:utf-8-*-" "Mysql.connector transaction summary: Connection.autocommit = 0

In the actual enterprise application environment, the single MySQL database is insufficient to meet the future business requirements. For example, if a server fails and there is no backup server to provide the service, the business will have to stop.

MySQL increases or decreases the specified time interval for all the current data tables (recommended ). The DATE_ADD () function adds a specified interval to a date. All data in the current table will be added one day later: UPDATE ACT_BlockNum SET

For Windows (x86, 64bit), upgrade MySQL 5.7.17 to an installation-free version. For more information, see mysql5.7.17. MySQL must be upgraded to version 5.5.3 or later to support Laravel 5.4's default utf8mb64 character encoding. Therefore, I