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
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.
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
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
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
Single line function -- PL/SQL
(1) Character function
Concatenate two strings, same as |
Change the first letter of the string to uppercase
Find the position of a string
Give the length of the string in characters
Posted on Sun, 31 May 2020 08:55:23 -0700 by rushenas
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
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:
declare @filename varchar(1024),
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
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
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
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