A brief discussion on many-to-many core architecture design

This article mainly introduces the basic class mapping and object relational mapping of Hibernate mapping in detail. It is of great practical value. Friends who need it can refer to it and recall some of the things we did when we didn’t learn ssh. When we created the database tables, first of all It is a database modeling E-R diagram, and then the relationship model is established through the entity model, and then the corresponding tables are established. There are three types of relationships between entities, one-to-one, one-to-many (or many-to-one), and many-to-many. Now, if we want to map the corresponding table based on the class, we can only map the database table through the relationship between classes and mapping files. We learn UML modeling. There are five relationships between classes, inheritance, implementation, association, dependency, aggregation/combination. The same is true for the relationship between entity classes in hibernate. We have implemented the code corresponding to different relationships. I am very familiar with it, so I am reviewing the knowledge about entity classes. The essence of Hibernate is Object Relational Mapping. ORM realizes saving object data into the database. In the past, we operated on the relational table and performed tasks such as addition, deletion, modification and query. Now we no longer perform

# on the relational table.

##1. Summary of courses about mapping files

Introduction: This article The article mainly introduces the basic class mapping and object relational mapping of Hibernate mapping in detail. It is of great practical value. Friends who need it can refer to it and recall some of the times when we did not learn ssh. When we created the database tables, the first thing was database modeling E-R. diagram, and then establish a relationship model through the entity model, and then create the corresponding table. There are three types of relationships between entities, one-to-one, one-to-many (or many-to-one), and many-to-many. Now, if we want to map the corresponding table based on the class, we can only map the database table through the relationship between classes and mapping files. We...

2. 5 recommended articles about header sorting

Introduction: hasOne and hasMany are Yii2's unique functions for multi-table related queries. It is recommended to use them when using multi-table related queries. This article mainly introduces the detailed usage of hasOne, hasMany and many-to-many related queries in Yii2. Friends who need it can refer to the preface. hasOne and hasMany are Yii2's unique functions for multi-table related queries. Multi-table related queries are usually used. It is recommended to use them when querying. Why? Because the results of related queries in this way will retain Yii2's own header sorting function,...

3. Detailed introduction to hasMany

Introduction: hasOne and hasMany are Yii2’s unique functions for multi-table correlation queries. Multi-table correlation queries are usually used. It is recommended to use them. This article mainly introduces the detailed usage of hasOne, hasMany and many-to-many related queries in Yii2. Friends who need it can refer to the preface. hasOne and hasMany are Yii2's unique functions for multi-table related queries. Multi-table related queries are usually used. It is recommended to use them when querying. Why? Because the results of related queries in this way will retain Yii2's own header sorting function,...

4. Detailed introduction to hasOne

Introduction: hasOne and hasMany are Yii2’s unique functions for multi-table correlation queries. Multi-table correlation queries are usually used. It is recommended to use them. This article mainly introduces the detailed usage of hasOne, hasMany and many-to-many related queries in Yii2. Friends who need it can refer to the preface. hasOne and hasMany are Yii2's unique functions for multi-table related queries. Multi-table related queries are usually used. It is recommended to use them when querying. Why? Because the results of related queries in this way will retain Yii2's own header sorting function,...

5. 10 recommended courses on mapping relationships

Introduction: This article mainly introduces the basic class mapping and object relational mapping of Hibernate mapping in detail. It is of great practical value. Friends in need can refer to it and recall some of the databases we built when we did not learn ssh. When creating a table, the database is first modeled as an E-R diagram, then the relationship model is established through the entity model, and then the corresponding table is established. There are three types of relationships between entities, one-to-one, one-to-many (or many-to-one), and many-to-many. Now, if we want to map the corresponding table based on the class, we can only map the database table through the relationship between classes and mapping files. We...

6. Detailed introduction to object mapping

Introduction: This article mainly introduces the basic class mapping and object relational mapping of Hibernate mapping in detail. It is of great practical value. Friends in need can refer to it and recall some of the things we established when we did not learn ssh. For database tables, the database is first modeled as an E-R diagram, and then the relationship model is established through the entity model, and then the corresponding tables are established. There are three types of relationships between entities, one-to-one, one-to-many (or many-to-one), and many-to-many. Now, if we want to map the corresponding table based on the class, we can only map the database table through the relationship between classes and mapping files. We...

7. Summary of the principles of database design

Introduction: The relationship between the original document and the entity can be one-to-one, one-to-many, or many-to-many. In general, they are a one-to-one relationship: that is, one original document corresponds to and only one entity. In special cases, they may be a one-to-many or many-to-one relationship, that is, one original document corresponds to multiple entities, or multiple original documents correspond to one entity. , (fine) database design principles

8. Detailed graphic explanation of RBAC user rights management database design in thinkphp

Introduction: RBAC (Role-Based Access Control, role-based access control) is the association of users with permissions through roles. Simply put, a user has several roles, and each role has several permissions. In this way, a "user-role-permission" authorization model is constructed. In this model, there is generally a many-to-many relationship between users and roles, and between roles and permissions. (As shown in the picture below)

9. Usage examples of hasOne, hasMany and many-to-many related queries in Yii2 (picture)

Introduction: hasOne and hasMany are Yii2-specific functions for multi-table related queries. It is recommended to use them when using multi-table related queries. This article mainly introduces the detailed usage of hasOne, hasMany and many-to-many related queries in Yii2. Friends in need can refer to

10. php Personnel Authority Management (RBAC )

## Introduction: RBAC (Role-Based Access Control, role-based access control) is the user Associate roles and permissions. Simply put, a user has several roles, and each role has several permissions. In this way, a "user-role-permission" authorization model is constructed. In this model, there is generally a many-to-many relationship between users and roles, and between roles and permissions.

[Related Q&A Recommendations]:

#php - Could you please explain the many-to-many relationship and insert data into the intermediate table? There are also benefits of setting up intermediate tables

Database-Mysql Why can’t foreign keys be many-to-many

Problems with PHP code design

python - Several issues with relationship definition in SQLAlchemy (one-to-one/many-to-many)

mongodb - Requirements for statistical queries on mongoose association tables

The above is the detailed content of A brief discussion on many-to-many core architecture design. For more information, please follow other related articles on the PHP Chinese website!