See you soon, why SHOW TABLE STATUS never updates

Did you tread a hole? 1. Problem Description 2. Problem Exploration 3. Summary 4. Extended Reading 1. Description of the problem A few days ago, the QQ group was discussing a delayed update of M ...

Posted on Sun, 07 Jun 2020 18:11:50 -0700 by TeamTJ

MyBatis integrates dual data sources

Sometimes in a project, there are situations where you need to connect two databases. This article will talk about how to use dual data sources (or multiple data sources) in combination with Spring and Mybatis. Background introduction The key to implementing multiple data sources in this article is the AbstractRoutingDataSource provided by Spri ...

Posted on Thu, 04 Jun 2020 11:09:39 -0700 by smallflower

A detailed explanation of view sequence synonym index in Oracle

1, View 1. What is a view In short, a view is a virtual table, a mapping of entity tables       When to use views In development, there are some table structures that do not want too many people to contact, so entity tables are mapped to a view. (simplified table structure) In the process of project, programmers main ...

Posted on Tue, 02 Jun 2020 07:40:40 -0700 by thomasanup

Day 58: getting started with Web development Django

by Aurora Today, I'd like to introduce Django, another web development framework of Python. It is an open-source Web application framework customized based on python. It originated from an online news web site at first, and then opened up in 2005. Django has large and comprehensive functions. It provides a one-stop solution, which allows devel ...

Posted on Sun, 31 May 2020 23:11:44 -0700 by captainplanet17

Detailed explanation of single line function operation in Oracle

Single line function -- PL/SQL (1) Character function Function number Say clearly  CONCAT Concatenate two strings, same as |  INITCAP Change the first letter of the string to uppercase  INSTR Find the position of a string  LENGTH Give the length of the string in characters   ...

Posted on Sun, 31 May 2020 08:55:23 -0700 by rushenas

type column parsing of explain

1,const Indicates that the execution step returns at most one row of data. const usually appears in the equivalent query of the primary key or unique index, such as the equivalent query of the primary key id of the t table:It can be considered that it is as fast as a rocket to locate a record by comparing the equivalence between the primary key ...

Posted on Sun, 31 May 2020 08:54:20 -0700 by a.heresey

SQL scripts for full and differential backup databases

In the work, SQL Job needs to be created to back up the database regularly. Now, the script is recorded as follows. 1. Full backup: -- FULL declare @filename varchar(1024), @file_dev varchar(300) declare @path varchar(1024) set @path = N'F:\Backup\Plan2\'; declare @extension_name varchar(16) set @extension_name = ...

Posted on Wed, 27 May 2020 09:00:31 -0700 by benwhitmore

SQL statement blocking P6SPY

Software introduction P6Spy is an open source framework that can be used to intercept and modify data operation statements in applications. Through P6Spy, we can intercept SQL statements, which is equivalent to a recorder of SQL statements, so we can use it for relevant analysis, such as performance analysis. P6SPY provides the following functi ...

Posted on Wed, 27 May 2020 07:33:48 -0700 by FeralReason

[12c] new features: This article will give you a detailed understanding of the automatic data optimization (ADO) of Oracle 12c database

Write in front Oracle 12c can realize information lifecycle management (ILM) through heat map and automatic data optimization (ADO). The first chapter introduces heat map. This chapter will expand automatic data optimization, and finally realize information lifecycle management through heat map and automatic data optimization. 1 automatic d ...

Posted on Wed, 27 May 2020 04:47:19 -0700 by Karamja

MySQL Pressure Test Tool

Mysqlslap: MySQL's own stress testing toolmysqlslap is the benchmark tool that comes with mysql. It queries data, has simple syntax, is flexible and easy to use. It can simulate multiple clients concurrently sending query updates to the server, gives performance test data, and provides performance comparison of various engines.mysqlslap provid ...

Posted on Tue, 26 May 2020 09:29:37 -0700 by Bramme