1, jdbc connection to mysql above 8.0
After the mysql version above 8.0 is updated, the corresponding jdbc connection has also changed.
First of all, we need to configure the mysql environment. It is recommended that you go to the Internet to find a tutorial and follow it. I won't talk about the installation and configuration of mysql here.
Posted by mjl4975 on Fri, 20 May 2022 03:06:37 +0300
python is a magical language. The magical place is that everything is an object, so if you don't have an object, you should be able to find true love here.
What is all objects? What is an object? What does it have to do with class?
In python, when we define classes, we often
We all know that this object is a paren ...
Posted by Stickdragon on Fri, 20 May 2022 02:57:07 +0300
For WeChat chat records, it can be achieved in two steps by collecting chat records and generating word clouds from chat data.
1. Chat record data collection
The most difficult part of the whole task is chat data collection. Due to the different difficulty of extracting chat records of QQ and WeChat, for QQ chat data, simply export it. For We ...
Posted by classic on Fri, 20 May 2022 02:13:12 +0300
Summarize some basic front-end knowledge. Some knowledge may be asked during the front-end interview, so making a record will also help others check. If there are any questions, you can point them out and actively correct them.
Variable types and calculations
What are the types of typeof in JS
console.log(typeof undefined); //undefi ...
Separating the interface components from the edited data and connecting them through the data source is a better way to deal with the interface and data. Qt uses the Model/View structure to handle this relationship. The basic structure of Model/View is shown in the figure.
The functions of each part are as follows:
Data (Data) is the ac ...
Posted by bschultz on Fri, 20 May 2022 02:01:21 +0300
UT writing rules https://zhuanlan.zhihu.com/p/424117483
1. Follow the AIR principle
A (automation): unit tests should be fully automated and non interactive.
I (Independence): unit test cases must not call each other or depend on the order of execution.
--------Counterexample: method2 needs to rely on the execution of method1 and take the e ...
1: simply select the best time O(n^2) average time O(n^2) worst time O(n^2) 2: Directly insert the best time O(n) average time O(n^2) worst time O(n^2) 3: Bubble sort best time O(n) average time O(n^2) worst time O(n^2) 4: Hill sort ＾ best time ＾ O(n) average time O(logn) worst time ＾ O(n^s) 1 < s < 2 ...
Posted by QuietWhistler on Fri, 20 May 2022 01:49:27 +0300
The lamp architecture based on apache is one of the mature enterprise website application modes and one of the highest market share in the market. Learning to deploy a basic lamp architecture can be the start of our in-depth study and understanding of the more complex architecture.
1, LAMP overview
LAMP architecture is one of the ...
Posted by ShimmyShine on Fri, 20 May 2022 01:48:27 +0300
1. What is a servlet?
2. Working mode of Servlet
3. What are the main types of servlets
4. Create a Servlet class and configure it to the server
4.1 create a Servlet class and inherit HttpServlet (created manually)
4.2 configuring servlet s in Tomcat (must be configured in web.xml)
4.3 automatic creation and configuration
Posted by vcarter on Fri, 20 May 2022 01:41:15 +0300
1, Environmental installation
The first is the installation of MySQL, which is directly installed only with apt get command (this method is recommended here, because it does not need to link the relevant path when compiling later programs)
sudo apt-get install mysql-server
After my installation, the relevant header files and dynamic lib ...
Posted by posidon on Fri, 20 May 2022 01:31:35 +0300