MySQL

Partial error codes _mysql.c:35:23:fatal error:my_config.h:no such file or directoryCompilation terminated.Error:command ' gcc ' failed with exit status 1The complete error message is as below Primary error Keywords: Error:command ' cc ' failed

MySQL Installation 1, download the MySQL source package through the official website. http://dev.mysql.com/downloads/Click MySQL Community Server, select Source Code, click Generic Linux (architecture independent), compressed download after TAR

MySQL does not have an integrated graphical interface management tool. For users, using the doc interface alone to operate mysql databases is very troublesome. Therefore, some mysql graphical management tools are commonly used, among them, navicat

BY default, MySQL sorts all group by col1, col2,.... The query method is as follows: specify order by col1, col2,... in the query ,.... If the statement explicitly contains an order by clause containing the same columns, MySQL can optimize it

There are two methods to modify the maximum number of connections in the mysql database. Today, we will analyze the features and differences between the two methods so that we can better maintain mysql.Method 1: Use commandsYou can use the set

1) for tables of the Myisam type, you can import a large amount of data quickly using the following methods. Alter table tblname disable keys;Loading the dataAlter table tblname enable keys;These two commands enable or disable the update of

[Root @ centos var] # service mysqld stopMySQL manager or server PID file cocould not be found! [FAILED]Solution:First, check the process. The code is as follows:Copy code [Root @ irxpert-test/] # ps aux | grep mysq *Root 10274 0.0 0.0 68160 1336

Today, I saw an article about the slow query speed when mysql has 1 million data records. In this article, we will discuss the optimization solution for this problem.Lab preparationHere I have prepared a table with 10 million data for testing. By

I. Syntax GROUP_CONCAT ([DISTINCT] expr [, expr...] [order by {unsigned_integer | col_name | expr} [ASC | DESC] [, col_name...] [SEPARATOR str_val]) It can also be simply understood Group_concat ([DISTINCT] field to be connected [Order by asc/DESC

Syntax format:UPDATE table nameSET field name = REPLACE (The field value before replacement,'Replace the previous keyword ','Keyword after replacement')WHEREField name REGEXP "replacing the previous field value ";Demo:(1) replace the content field

MySQL can use multiple engines. When we choose to use the InnoDB engine, the ibdata1 file will become larger and larger over time, occupying a large amount of disk space.So what are stored in ibdata1 and why are they getting bigger and bigger? First,

Slow_query_log is a parameter that records SQL execution for more than a certain period of time.Slow query log related variables1. Command line parameters:-- Log-slow-queriesSpecifies the location where the log file is stored, which can be null, and

Case 1: Identify duplicates directly-- Find records with duplicate IDs in the table and calculate the number of records with the same IDsSelect id, count (id) from @ table group by id having (count (id)> 1)Group by id:Select id, count (id) from @

Causes of fragmentation(1) the storage of a table is fragmented. When a row of content is deleted, the space in the row is blank and left blank. A large number of delete operations are performed within a period of time, this will make the blank

After using the mysqldump command to export the MySQL database, the following commands are often used when importing the database. The code is as follows:Copy code Mysql -- default-character-set = utf8-u root-p dbname However, when the exported

Database recovery error: Due to Character set problems, the default encoding of the original database is latin1, and the encoding of the newly backed up database is utf8, leading to recovery errors.[Root @ hk byrd]

If you delete a mysql table in a large scope, it is better to optimize the table, which will be faster. I have written a similar article for the myisam storage engine. Please refer to: instance description optimize table is very important when

This article introduces how to use the group_concat function in MySQL through examples, such as select group_concat (name ).Group_concat function in MySQLThe complete syntax is as follows:Group_concat ([DISTINCT] field to be connected [Order by

The first step is to import the csv file to mysql. The import function of the client provided by mssql is not used. Because this function is too pitfall, if you try N methods, an error is still reported. Therefore, convert it to mysql for