Relationship many to many with three tables

General
1

I have a relationship many to many. How to refer to the table A, picking up the records of table AB? Do I need an active property in the middle table. In swift.

2

Hi Ítalo,

Please provide a more detailed schema definition and some sample code you’ve been trying to use.

3

Using Swift API. So I would like to see table A, taking the records of AB table

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4

So your relations are:

  1. A -> AB
  2. B -> AB
    Right?
    And what you want is to query objects from table A AND from table B? With what conditions?
5

Yes. Bring table “A” records only if the active property of the table “AB” is true

6

I have a table “User” and a table “knowledge.” A user has a lot of knowledge, and knowledge has many users, then have the user_knowledge table. In the table user_knowledge have the “active” property. I want the records of the user table that has records in the table user_knowledge with active property to true

7

You can try to use this where clause:

AB[a].active='true'

and query A table:

Backendless.Persistence.of( A.class ).find( query)

This is described in more detailed on this doc page: https://backendless.com/documentation/data/js/data_relations_retrieve.htm#subsetofchildren

8

Hello, I have simmilar problem, in this case, how can I recieve all Users that have a certain knowledge? In other words A - AB -B.

9

Very good, solved my problem. Thank you Sergey.