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1.mysql use a MySQL plugin from mysqludf to implement calling external programs and system commandsDownload Lib_mysqludf_sys Program: Https://github.com/mysqludf/lib_mysqludf_sys2. Installation instructions: 2.1 Query MySQL plugin path:In MySQL,

What is a trigger Features and functions Example: Create a trigger, record a table's increment, delete, change operation record Disadvantages What is a triggerSimply put, a table has something (INSERT, delete, update operation), and

# Job content ' 1, query the name of all the courses and the corresponding teacher name 2, query the student table of male and female students each have how many people 3, query physical results equal to 100 of the student's name 4, query average

1, Connection MySQL format: mysql-h host address-u user name-P user Password1. Connect to MySQL on this machine. First open the DOS window, then enter the directory Mysql\bin, and then type the command Mysql-u root-p, enter after the prompt you to

After work in the morning, MySQL server encountered a small problem, during the troubleshooting process to view the MySQL error log process found that several InnoDB tables could not be opened, using DESC to view the table structure hints table on

1. Characteristics of the index 1.1 accelerating the retrieval of conditionsThe query slows down as the amount of table data becomes larger, uses the index on the table's criteria fields, quickly navigates to records that might satisfy the criteria,

Basic QueryFirst create a Students student table, add fields and insert data as followsTo create a stored procedure with no parametersSee the number of studentsDROP PROCEDURE IF EXISTS select_students_count; DELIMITER;; CREATE PROCEDURE '

To see if it is turned on:Show variables like ' Event_scheduler ';If off is displayed, enter the following statement to open:Set global Event_scheduler = on;Note: Although the event is turned on using the set global Event_scheduler = ON statement,

Before always write stored procedures on the MSSQL, not written on the MySQL, but also basically no use, today need to use MySQL, research, the project needs to write a part of the stored procedures, write a summary of the work. This does not give

--Query the partition of a tableSelect as from--time period for creating partitionsCREATE PARTITION FUNCTION part_func_userlog (datetime) as RANGE left for VALUES ('20120709 23:59:59.997', '20120710 23:59:59.997', '20120711 23:59:59.997', '20120712

if exists (SELECT * from dbo.sysobjects WHERE id = object_id (N ' [dbo].[ F_getdbpath] ') and xtype in (n ' FN ', n ' IF ', n ' TF '))Drop function [dbo]. [F_getdbpath]GO/*--get the file directory of the database@dbname Specifies the name of the

Supports multi-medium format JS keyboards /* * JavaScript Virtual Keyboard (ATM-style numpad variant), version 2.3 * * Copyright (C) 2006-2007 Dmitriy Khudorozhkov * * This software is provided "as-is", without any express or implied warranty. * In

Using MySQL UDFs and Trigger to operate MemcachedUDFs is short for UserDefinedFunctions, indicating MySQL user-defined functions, applications can use these functions to access data written or obtained by Memcached from databases of MySQL or later

Many people use different things to solve difficulties in easy language. If a stored procedure is used, it is similar to a general programming language. Here we use the SQL idea to implement it once in MySQL. MySQLdroptableifexistsn1;

Table partitions are only recently known. I used to split tables to achieve hundreds of millions of data records. Let's introduce how to create and use mysql table partitions, I hope this will help you.Test and use of table partitions. The main

Example 1: A simple Stored Procedure cursor instanceCopy codeThe Code is as follows:DELIMITER $Drop procedure if exists getUserInfo $Create procedure getUserInfo (in date_day datetime)---- Instance-- Stored procedure name: getUserInfo-- Parameter:

If a database exists, delete it. If a database exists, delete ifexists (selectnamefrommaster .. sysdatabaseswherenamein (db_name) dropdatabasedb_namego -- determines whether the specified stored procedure exists. If yes, delete ifexists (select *

One of the stored procedures-creating a simple Stored Procedure I. Stored Procedure Stored Procedures (Stored Procedure) are a set of SQL statements for specific functions in large database systems. They are compiled and Stored in the database.You

1. in SQL Server, use select object_id ('tempdb .. # temptable') to determine whether a temporary table has been created. (The returned value is an integer. If no value is set, the return value is null) Tempdb is a database that stores temporary

This is the automatic deployment of the standalone version. For manual deployment, refer to my other article: Http://blog.csdn.net/sheismylife/article/details/6737127 First download the mongodb-linux-x86_64-2.2.0.tgz, decompress it and put it under