Summary of learning content I

Java

This week I mainly learned the construction method and this function. The
construction method is to initialize the object and assign the value to the object. It is divided into two types: non-parameter structure and parametric structure.
The form is:

No parameters:

pubilc 函数名 {}

Participants:

public 函数名（变量） {
	this.变量名 = 变量
}

python

Python learned pymsql this week.
Specifically, the database is created in mysql and then added, deleted, modified and checked with python statements.
Specifically divided into 4 steps

1. Create connection object
2. Get the cursor object
3. Input addition, deletion, modification, query sentence
4. Close object

mysql

Mysql learned about views this week.
Views are similar to queries, but views can be modified. Views store not data but SQL statements when they are created. To call the created view is to call the string of SQL statements.
Create a view:

create view 视图名 as select查询语句

Modify the view:

alter view 视图名 as 查询视图

Delete view:

drop view 视图名