MySQL Three table connection query

Permission table (permission) 10

Field name	Type	Constraints	Describe
AuthorityID	Integer	Pk NOT NULL	Permission Serial ID PK
Usernameid	Int	NOT NULL	User name ID FK
FunctionID	Integer	NOT NULL	function ID FK
Lookpermission	Int	NOT NULL	Browse
Addpermission	Int	NOT NULL	Add to
Editpermission	Int	NOT NULL	Edit
DeletePermission	Int	NOT NULL	Delete
Checkpermission	Int	NOT NULL	Audit
Againstrcheckpermission	Int	NOT NULL	Anti-Audit
Statementpermission	Int	NOT NULL	Report

Function Module table (functioncomponents) 3

Field name	Type	Constraints	Module Name Description
Functioncpid	Integer	Pk	function ID PK
Fundescribe	Varchar (100)	NOT NULL	Module name
Otherinfo	Varchar (500)	NOT NULL	Note

User table (UserInfo)

Field name	Type	Constraints	Describe
Userno	Integer	Pk NOT NULL	Permission Serial ID PK
UserName	VARCHAR2 (20)	NOT NULL	User name ID FK
Userpwd	VARCHAR2 (20)	NOT NULL	Browse
Role	VARCHAR2 (20)	NOT NULL	Browse

To query the permissions of a user's corresponding function

At first, I was using a subquery, not implemented

Select Userno, Userinfo.username, Userinfo.userpwd, Fundescribe, Lookpermission, Addpermission, EditPermission, DeletePermission, Checkpermission, Againstrcheckpermission, statementpermission from UserInfo, permission, Functioncomponents

Switch

Select Userno, Userinfo.username, Userinfo.userpwd, Fundescribe, Lookpermission, Addpermission, EditPermission, DeletePermission, Checkpermission, Againstrcheckpermission, statementpermission from UserInfo, permission, Functioncomponents GROUP BY Userno

The same is true!

After that, the three tables are connected in a query

Create View ' userfunpermission ' as

Select Userno, Userinfo.username, Userinfo.userpwd, Fundescribe, Lookpermission, Addpermission, EditPermission, DeletePermission, Checkpermission, Againstrcheckpermission, statementpermission from UserInfo, permission, Functioncomponents

OK!

MySQL Three table connection query