MySQL

MySQL connects to the database through a third-party client tool. Chinese characters in the table are garbled, but there is no problem with the command line tool of MySQL. Character Set variables:> Show variables like '% character %

1. Test data table: mysql> select * from T1; + ------ + ------- + | ID | Name | + ------ + ------- + | 1 | name1 | + ------ + ------- + 1 row in SET (0.00 Sec) mysql> select * From T2; + ------ + ------- + | ID | Name | + ------ + ------- + |

Scenario settings The client is an Android mobile phone. After logging on to the client, you want to save the online status of the client (server). Each online user has a corresponding checksum value, which needs to be verified each time an

When using Perl to write data to a MySQL database through DBI, if the content encoding method is inconsistent with that of the system, garbled characters will occur in the database. The result is as follows: After connecting to the database, set the

1. Connection operations and Set Operations (continued) Since MySQL does not support full join, I can do this: Select * FromALeft JoinBOnA. ID=B. IDUnionSelect * FromARight JoinBOnA. ID=B. ID A. First find the left join B. Right join

By default, MySQL search is case-insensitive (however, some character sets are always case-sensitive, such as Czech ). This means that if you use col_name like 'a % 'for search, you will get all columns starting with a or. If you want to make the

Connect to MySQL in Asp.net, use MySQL. Data. dll, complete ADO. Net access mode, and perform operations as conveniently as SQL Server MySQL. Data. dll: http://dev.mysql.com/downloads/Http://free5.ys168.com /? Dotnetly UsingMySQL. Data.

MySQL on the test machine fails today and cannot be started. I found the Linux expert TJ to help find the cause: the log file is too large, resulting in/data no space. By default, log files are stored in/data/MySQL/data (MySQL is mounted on/data

When group_concat and Concat are mentioned above, if the column value is null, the value after Concat is null. Another problem is found. If Column A is null and column B is null, the sum of the number of records of column A <> B and A = B is not

MySQL connector/net makes. NET + MySQL development more and more convenient. The official introduction of MySQL connector/net is as follows: Connector/NET enables developers to easily create. NET applications that require secure,

Upgrade rails from 2.1 to 2.2 today to runProgram. Run rake DB: The migrate test shows no such file to load -- MySQL Finally, follow the steps below to solve the problem. 1. Gem install MySQL 2. Copy libmysql. dll in the MySQL bin directory

To store and read the owl ontology to MySQL, you must first configure the environment and add Jena packages to the project. It is worth noting that the MySQL driver and version must be consistent. I used protege to create an owl ontology, read it

Java has been tested yesterday afternoon, and there is still a database principle this afternoon, so I have no plans to write anything. I came back this afternoon and played mysql. I used it before, I used MYSQL as a source code from the Internet.

MySQL is currently the most popular multi-threaded, Structured Query Language (SQL) database server. Most PHP websites use this database in the background.MySQL has high execution performance, fast operation speed, and is very easy to use. It is a

A while ago, I visited MySQL through oracle in the company. The test environment is centos5_x64, oracle10g_x64, and mysql5.Share some experiences with you! 1. First, install the mysql client software on the computer where oracle is located, and

1. Show Character Set [like 'pattern'] Show all available character sets Mysql> show character set like 'gbk'->; + --------- + signature + ----------------- + -------- + | charset | description | default collation | maxlen | + --------- +

Execute loop operations with the cursor Drop   Procedure   If   Exists Sp_opr; Create   Procedure Sp_opr () Begin /**/ /*Define variable 1*/ Declare _ Err_code Char ( 8 ) Default   '' ; /**/

When creating a table, the IP field is set to varchar. However, to index the table to improve the efficiency of combining it with other tables, we intend to change it to Char, the modification failed.Finally, we found that to change all the varchar

Backup Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--> Mysqldump - Uroot - Proot Goodluck > ' /Media/sda7/gookluck. SQL ' I failed to restore the database successfully in Windows

Previously, rails2.2 installed the MySQL driver by default, and then changed to sqlite3 by default. If you are connected to MySQL, you need to install it on your own.When learning open-source systems, we found that some rails3 applications directly