MySQL

Reinstalling the system is always a good solution, but who would like to do so :( Later, I did not intend to find that the uninstallation was not completely caused by the uninstallation. The following describes how to unmount MySQL 5.1: 1. add

1. Data capacity: the total number of data records and the total number of bytes of each data record within 1-3 years; 2. Data items: whether there are large fields and whether the values of those fields are updated frequently;3. SQL condition

1. Add default-character-set = gb2312 to the [client] In my. ini under the MySQL installation directory. [Client]Default-character-set = gb2312Port = 33062. Copy my. ini to the C root directory and change the name to my. CNF. 3. When configuring

The following figure shows the data inserted into the tuangou table: Id web city type1. Beijing Food & Beverage2. Shanghai leisure and entertainment3% group Tianjin Food & Beverage4. Online Shopping in ShenzhenDiscount coupons for Shijiazhuang6%

1. Use the explain statement to view the analysis resultsFor example, explain select * from test1 where id = 1; the columns of id selecttype table type possible_keys key key_len ref rows extra are displayed. Where, Type = const indicates that the

MySQLDatabaseVarcharWhat is the maximum length? In fact, this is not a fixed number. The length of varchar isRestriction rules. In this article, we will introduce the varchar restriction rules in the MySQL database, and describe the restriction

SQL _mode = "", that is, the high performance should be improved if the MySql mode is not set (such as no input detection, error prompt, or syntax mode check), but the following problems exist: If an inappropriate data is inserted (the error type is

Copy codeThe Code is as follows: BEGIN DECLARE '@ I' int (11 ); DECLARE '@ siteCount' int (11 ); DECLARE '@ sqlstr' VARCHAR (2560 ); DECLARE '@ sqlinsert' VARCHAR (2560); // DECLARE the variable above Select count (0) into '@ siteCount' FROM

Modify my. ini and add Default-storage-engine = INNODB The red font indicates the engine name to be specified. Use SQL statements to modify the engine of a table: Alter table tableName type = InnoDB My. ini file for reference (http://www.my400800.

At first, I did not expect that the data of the 10 million yuan would be inserted into a single number for only 2 w in half an hour. Later, an SQL batch insert statement was improved. Copy codeThe Code is as follows: -- Insert into table (mobile)

Recently, some troubles have occurred. The newly installed official PHPwind6.0 community found that the mail addresses of many Members seem to be filled out randomly when importing the previous Member account information, in PHPwind5.5, mail address

The following error occurs: "Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file', or the Master/Slave database is not synchronized due to data clearing. The

1. Are you still using a primary key for association between two tables?For example, there are two tables, one for news topic and one for news. Now the two tables need to be associated, I think most people must create a news topic id in the News

1. View Indexes (1) Unit: GB Select concat (ROUND (SUM (index_length)/(1024*1024*1024), 2), 'gb') AS 'total Index size' FROM information_schema.TABLES WHERE table_schema LIKE 'database ';+ ------------------ +| Total Index Size |+ ------------------

After ping and route, it is found that network communication is normal, and local connection discovery on the mysql machine is very fast, so the network problem is basically ruled out. I have encountered such a problem before, but I don't know how

Statement: alter table tableName engine = InnoDB; Tables Used Copy codeThe Code is as follows: create table if not exists 'test '( 'Id' int (10) not null auto_increment, 'Websitename' varchar (200) character set utf8 not null, 'Websiteurl' varchar (2

1. Connect to the Mysql database using ADO. NET After searching for information on the Internet, there are three methods to connect to the mysql database on. net: Method 1: Use the MYSQL access component released by CoreLab to reference the

Method 1: Copy codeThe Code is as follows: Mysql_connect ('','',''); Mysql_select_db (''); $ Rs = mysql_query ('show tables '); While ($ arr = mysql_fetch_array ($ rs )){ $ TF = strpos ($ arr [0], 'class _'); If ($ TF = 0 ){ $ FT = mysql_query

Error No:2003 Problem Analysis: Unable to connect to the MySQL server, possible situation: 1. the MySQL service is not started. It is generally caused by the failure of MySQL to start in case of exceptions, such as no available disk space or

Note: unless the table has a primary key or UNIQUE index, using a REPLACE statement is meaningless. This statement is the same as INSERT, because no index is used to determine whether other rows have been copied in the new row. [Separator]The