Let’s talk about the current status, prospects and opportunities of Record examples

We have seen how to use Active Record (AR) to get data from a single data table. In this section, we explain how to use AR to connect multiple related data tables and retrieve the joined data set. To use relational AR, we recommend defining primary key-foreign key constraints in the tables that need to be related. These constraints can help ensure the consistency and integrity of related data. This example introduces how to use Active Record for multiple related tables by modifying the database-Query Builder example of Yii Framework Development Tutorial (25). Before we use AR to perform related queries, we need to let AR know how one AR class is related to another. The relationship between two AR classes is directly related through the relationship between the data tables represented by the AR classes. From a database perspective, there are three relationships between tables A and B: one-to-many (such as tbl_user and tbl_post), one-to-one (such as t

1. PHP Development Framework Yii Framework Tutorial (27) Database-Associated Active Record Example

Introduction: We have learned how to use Active Record (AR) to obtain data from a single data table. In this section, we explain how to use AR to connect multiple related data tables and retrieve the associated data. Set.

##2. PHP Development Framework Yii Framework Tutorial (26) Database-Active Record Example

Introduction: Use Java or .Net to write database applications. Many people have used Hibernate (or NHibernate), which can greatly simplify database programming and read and write databases in the form of objects. (ORM), Active Record (AR) provided by Yii is also a popular object-relational mapping (ORM) technology

[Related Q&A recommendations]:

The above is the detailed content of Let’s talk about the current status, prospects and opportunities of Record examples. For more information, please follow other related articles on the PHP Chinese website!