How to handle additional columns in join tables when using Symfony?
datamodel, doctrine-orm, symfony
Solution
You want to set a property of the relation. This is how it's done in doctrine: doctrine 2 many to many (Products - Categories)
I answered that question with a use case (like yours).
This is an additional question / answer which considers the benefits and use cases: Doctrine 2 : Best way to manage many-to-many associations
Problem
Let's assume I have two Entities in my Symfony2 bundle, `User` and `Group`. Associated by a many-to-many relationship. ``` ┌────────────────┐ ┌────────────────┐ ┌────────────────┐ | USER | | USER_GROUP_REL | | GROUP | ├────────────────┤ ├────────────────┤ ├────────────────┤ | id# ├---------┤ user_id# | ┌----┤ id# | | username | | group_id# ├----┘ | groupname | | email | | created_date | | | └────────────────┘ └────────────────┘ └────────────────┘ ``` What would be a good practice or a good approach to add additional columns to the join table, like a created date which represents the date when `User` joined `Group`? I know that I could use the `QueryBuilder` to write an `INSERT` statement. But as far as I have not seen any `INSERT` example of QueryBuilder or native SQL which makes me believe that ORM/Doctrine try to avoid direct INSERT statements (e.g. for security reasons). Plus as far as I have understood Symfony and Doctrine I would be taken aback if such a common requirement wouldn't be covered by the framework.