MySQL

Original address: http://www.cnblogs.com/yuwensong/p/3955834.htmlUnder Window1. Export the entire databaseMysqldump-u user name-p database name > exported file nameMysqldump-u dbuser-p dbname > Dbname.sql2. Export a tableMysqldump-u user name-P

RAND ()--Returns a random number between 0 and 1Floor (value)--Rounding downCeil (value)--Rounding upCOUNT (Field/*); --When the parameter is a field, the number of records in that field in each group is counted, but NULL is not counted; when the

Case: MySQL can only log on localhost, use #mysql-uroot-p-hip-p3306 cannot log inWorkaround:1. Change the table method. It may be that your account is not allowed to log on remotely, only on localhost. This time, as long as the computer on the

First, Version introductionCommunity Edition: Free, personal use, can not be commercially used, out of the problem of their own solution, no technical supportEnterprise Edition: Charges, commercial use, emphasis on basic services, the number of CPUs

First, create a viewCreate [algorithm = view algorithm] View name as SELECT statement; --can be any query statement (normal query, connection query, union query, subquery)There are three view algorithm options:1. Undefined: The default setting,

Tag: connection where SQL join Select also returns NULL for outer JOINSELECT * from test1 a,test2 b where a.no=b.no;; Internal connectionSELECT * FROM Test1 a ieft join test2 B on a.id=b.id; left outer connectionSELECT * from Test1 a right joins

Database update and Backup is one of the basic functions of operations, and here is the operation of the statement to do a tidy, not regularly updated.1) Database backup statementsMYSQLDUMP-H Database IP address-u user name-p password ABC XYZ >

MySQL replication: The process of replicating all changes on one DB instance to another database server instanceCharacteristics:1. No change does not matter copy; change is the root of replication and the data source2. All changes: means that all

The MySQL database provides two types of indexes, and if not set correctly, the efficiency of the index is compromised but the problem is completely unknown.[C-sharp]View PlainCopy CREATE TABLE Test ( ID INT not NULL, Last_Name

Today, when programming, the Chinese stored in the MySQL Chinese garbled problem, the online search data finally resolved:The first thing you just opened is a question mark:Then I looked up the data, first I read my MySQL encoding formatSo according

Reprint Address: http://lobert.iteye.com/blog/1955841Get a table some days ago, nearly 4000w data, no index, primary key. (It's definitely a talent to build this watch.)This is a log table, recorded in the game the output and consumption of items,

is equivalent to or in MySQL, so why in is recommended, in is a bit like this: 1. The In operator syntax is clearer and more intuitive when using the long legal option list; 2. When using in, The order of calculation is easier to manage (because

Stored ProceduresWhat is a stored procedure??In simple terms, a stored procedure is a collection of one or more SQL statements that are saved for later use .It's more like the concept of a function in our programming language.In a programming

When you install MySQL, there is no root password, or add other users, the default is no password, at this time we can mysql-uroot directly into the MySQL command interfaceIf you want to add the root password, use Set password for ' root ' @ '

MySQL create user and authorization methodFont: [Increase decrease] Type: Reprint time: 2012-11-10 I want to commentMySQL in the creation of user and authorization implementation method, for the first contact with MySQL friends can refer to betting:

InnoDB table. frm: Table structure. IBD: Table space (data and index)SHOW ENGINESSHOW TABLE STATUSHow the program language connects to the database:Dynamic SQL: Establishing a connection to a database service by function or methodEmbedded

At the end of the year, do a routine inspection for MySQL.Preface: Routine inspection is a required item before the holidays. It performs a round of comprehensive health check on servers. On the one hand, it can ensure the stability of servers

Class and ObjectObject Oriented (OO ). At first, "object-oriented" refers to the use of encapsulation, inheritance, polymorphism and other design methods in program design. Now, the object-oriented thinking involves various aspects of software

Mysql permission management Significance of database permissions: In order to ensure that the business data in the database is not illegally stolen by unauthorized users, various restrictions need to be imposed on Database visitors. There are three

Master-slave replication for mysql Learning This article uses mysql5.5 centos6.5 64-bitI. Role of master-slave Replication 1. If there is a problem with the master server, you can quickly switch to the slave server. 2. Applications with low