MySQL

Data: A db,2000 table, 2000 Tabular data, 30 column per record, and an average of 4.3w records per sheet, totalling 86,388,670 records. Machine: Linux 64bit 8G memory 4 core Intelx3320@2.5ghz Basic ideas: Copy Code code as follows:

In a Debian environment, completely solve the problem that MySQL cannot insert and display Chinese Linux under MySQL insert Chinese display garbled solution Mysql-uroot-p return Enter password Enter the MySQL view status as follows: The

The constant global event_scheduler of MySQL must be on or 1 for the timer to function. --See if the timer is turned on Show VARIABLES like '%sche% '; --Open Timer 0:off 1:on SET GLOBAL event_scheduler = 1; --Create Event --Automatically calls

First of all to declare: Under normal circumstances, to modify the MySQL password, authorization, is required to have the root of MySQL permissions. Note: This operation is at the win command prompt, phpMyAdmin is also applicable. User: Phplamp user

If you are accustomed to using Windows database, that is, in the graphical interface to manipulate the database, then when you operate on the command MySQL will be unfamiliar, in fact, as long as you master some basic commands, and often used,

Example 1, a simple stored procedure cursor instance Copy Code code as follows: DELIMITER $$ DROP PROCEDURE IF EXISTS getuserinfo $$ CREATE PROCEDURE GetUserInfo (in Date_day datetime) -- --Example --Stored procedure name:

1.order by Rand ()The data is very slow, the randomness is very good, suitable for very small amount of data. Copy Code code as follows: SELECT * FROM table_name as R1 JOIN (select ROUND (RAND () * (select ABS (MAX (ID)-min

RegexpExample 1. The query field contains data that is not in English Copy Code code as follows: SELECT * From ' M_user ' WHERE ' Emp_no ' REGEXP ' [^-~] ' =1 Column 2. So I can get all the English-free Copy Code

The day before yesterday because the work required me to take a random few records from a database of 5W records, here I am directly using the MySQL rand by function to direct, thousands of records okay, but if the tens of thousands of feeling to a

MySQL calculates a two-date time difference function Timestampdiff usage: Grammar: Timestampdiff (INTERVAL,DATETIME_EXPR1,DATETIME_EXPR2) Description Returns the integer difference between a date or datetime expression Datetime_expr1 and

One The following parameters in the php.ini are preceded by the ";" Remove: Copy Code code as follows: ; Extension=php_dba.dll ; Extension=php_gd2.dll ; Extension=php_mbstring.dll ; Extension=php_mcrypt.dll ;

Copy Code code as follows: $cfg _dbhost = ' localhost ';//mysql host $cfg _dbname = ' sq_test ';//Database name $cfg _dbuser = ' root ';//database user name $cfg _dbpwd = ' jb51.net ';//database user password $cfg _db_language = ' UTF8 ';//

This example realizes the communication function of the client through thinkphp combining Ajax with MySQL, as follows: 1, using JS Ajax local refresh function, each refresh the database read out of the new record inserted into the page display area,

DROP FUNCTION IF EXISTS ' getpy '; DELIMITER;; CREATE FUNCTION ' getpy ' (in_string VARCHAR (65534)) RETURNS mediumtext CHARSET UTF8 BEGIN DECLARE tmp_str VARCHAR (65534) c Harset GBK DEFAULT '; #截取字符串, each time the intercepted string is stored in

Baidu has consulted some information, and combined with some of its own experience, the following solutions are adopted: Copy Code code as follows: $idlist = '; For ($i =1 $i if ($i ==1) { $idlist =mt_rand (3,25216); } else{ $idlist =

A recent study on C + + connection database. When MySQL is installed, the Include folder under its installation directory does not find Libmysql.lib. This has been studied and found to be due to the fact that when MySQL is installed, There is no

MySQL MySQL lost connection to server during query problem resolutionReason: In the query MySQL database, or modify the larger table when this situation occurs;Google's:Programme 1. Add a row of settings skip-name-resolve under the MySQL profile

Import java.sql.*; Import Java.text.DateFormat; Database query public class Selecttable {String dbdriver= "com.mysql.jdbc.Driver"; String dburl= "Jdbc:mysql://localhost:3306/sss"; Change string username= "root" according to the actual

1. Open the terminal, input: cd ~ Will enter the ~ folder 2. Then enter: Touch. Bash_profile When a carriage return is executed, 2. Re-enter: Open-e. bash_profile This file is opened in TextEdit (if you have not previously configured an

Today, a friend asked me how to optimize MySQL, I follow the thinking of a bit, probably rough can be divided into 21 directions. There are some details (table cache, table design, index design, program-side caching, etc.) first, for a system, the