MySQL

Add foreign keyAlter table data add constraint data_fk_pack_inForeign key (pack_in)References package_io_link (in_id)On Delete set default on update no action;   Create a table Create Table temp (Id int,Name char (20 ),Foreign key (ID) References

# Cd/home/tmp (enter the directory of the compressed package)# Groupadd MySQL (create a MySQL Group)# Useradd-G MySQL (create a MySQL user in the MySQL Group)# Tar-zxvf mysql-5.0.37.tar.gz (extract MySQL source code, bz2 compressed package, please

During this period, the MySQL database performance was significantly reduced, iowait reached 30, and the response time was significantly longer. view through show processlist and find that many sessions are processing sort operations, debugging and

MySQL memcached udfsUdfs stands for user-defined functions (udfs), which are user-defined functions of MySQL. Applications can use these functions to access memcached writes or obtain data from databases of MySQL or later versions. In addition,

A few days ago, the company came to a new person and accidentally kicked off the power supply. At that time, my machine was still running the server program. The above is the background. When I restart the service, I find that connection to the

Linux selected in the last semester, because the last semester is relatively time-consuming, so there is no time to sort it out, now it is well organized, keep it for future use. 1. Download Apache libxml2 PHP MySQL files. 2. install Apache Tar-zxvf

No reading or reading. It will only be written according to the existing code .... Dumb Compile an imgstore table created in SAE. The structure of the imgstore table is as follows: $mysql = new SaeMysql();$mysql->setCharset(GBK);$sql = "SELECT *

Connecting to the MySQL database using C language involves two steps:1. initialize a link handle structure;2. actually connectFirst, use mysql_init to initialize the connection handle:# Include MySQL * mysql_init (MySQL *);Generally, if you pass

Reprinted address: Click to open the link I am using Sina Sae as a jquery microblog, but the connection to MySQL has always been faulty. Because the saemysql Class Based on MySQL module provided by Sina Sae is not used MySQL connection information

MySQL: 1. do not export the statement for table creation, because the table has been created: exported by default, drop table first and then create table; 2. add ignore to the exported insert statement to allow repeated execution: Ignore is not

I heard that Linux is case sensitive for a long time. I didn't expect it to be case sensitive in databases this time. Generally, the development is on Windows platforms and case-insensitive. But in Linux, you need to pay attention to it. MySQL

The MySQL version used in this article is 5.1.48 Select SQL _no_cache * from one where ID #0 my_qsort2 (base_ptr=0x1b2176c0, count=4, size=8, cmp=0x869220,cmp_argument=0x4670ea38) at mf_qsort.c:115#1 0x00000000008690ea in my_string_ptr_sort

MySQL proxy Learning (2) -- status transfer In the previous section, we have known the listen FD callback function network_mysqld_con_accept. This function is responsible for connecting the accept client to network_socket_accept, and then enters

Content transferred from Sohu gulei PPTGains from viewing MySQL source code 1. provide theoretical basis for Optimization2. Learn the algorithms and ideas for solving the problemFilesort algorithm (Sorting Algorithm) 1. Read all data to be sorted 2.

Content transferred from Sohu gulei PPT Originally edited from old gold: http://www.mysqlops.com/2012/05/15/mysql-sql-analyze.html Preface:• Without accumulating steps or even thousands of miles; without accumulating small streams, there is no way

Temporary table This article carries the following questions (Investigation ): Why can the same name be used? Which table is processed first? In master-slave backup, how does one deal with two different sessions, the temporary table with the same

  MySQL has entered the Oracle product system and gained more R & D investment. The next-generation MySQL product mysql5.5 is coming soon. Compared with the previous version 5.1, it will be improved in many features, which are summarized as follows:

I. objective of setting swap in the operating systemA necessary condition for running a program is sufficient memory, and the memory is usually a resource that is relatively tight in the system. To meet the requirements of more programs, the

To implementUnlimitedLevel Classification, recursion is generally the first and easiest way to think of, but recursion is generally considered a resource-consuming method, so many systems do not consider using recursionThis article uses the database

Self-opening place   MySQL has a function to log down and run slow SQL statements. This log is not available by default. To enable this function, modify my. CNF or start MySQL.When adding some parameters. If you modify it in my. CNF, add the