Detailed introduction about hasMany
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, as well as the id storage value of the input in CheckboxColumn. As for whether there are other benefits, everyone needs to dig out. The author has discovered these two so far. A common benefit. There are no other related queries, such as yiidbQuery query or native SQL statement query. When the query is displayed in the list, the header of the table is black. Yii2's hasOne and hasMany multi-table related queries, whether it is a document or an article, can actually easily find the reference master. But why did the author write this article? The idea is actually very simple, because
1. Detailed introduction about hasOne
##Introduction: hasOne and hasMany are unique to Yii2 Functions used 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,...
2. hasOne, hasMany and many-to-many relationships in Yii2 Query usage example (picture)
3.
yii2 Update multiple related tables Field
Introduction: There are two tables account and user. The account table has fields mobile and bind. The user table also has mobile and bind fields. The account class and user The class uses hasMany to associate through uid. When the account table mobile.bind is updated, the user table association is automatically updated. Please tell me, automatic update...[Related Q&A recommendations]:
laravel ORM problemphp - yii2 Association table updates multiple fieldsphp - Yii Related tables with optimized queries to avoid N+1 query questionssql - Why do ORM frameworks (Hibernate of JAVA and Sequelize of Node.js) have to have a relationship to perform join queries? ?php - laravel eloquent How to build a reply to comment
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