Connecting models.
WHAT KINDS EXIST
One record having one other One record having many A record belonging to another Many related to many, through an intermediate table Relationships through an intermediate model
WHAT TO DEFINE
Both directions, where both are used.
WHAT NAMING CONVENTIONS ASSUME
Predictable key names.
Where yours differ, state them explicitly.
WHAT RELATIONSHIPS ENABLE
Accessing related records naturally Querying based on related records Creating related records through the parent
WHAT TO BE CAREFUL WITH
Accessing a relationship inside a loop.
WHY
Each access issues a query.
WHAT THAT PRODUCES
One query for the list, then one per item.
THAT IS THE COMMONEST PERFORMANCE PROBLEM IN LARAVEL APPLICATIONS
WHAT TO DO ABOUT IT
Load the relationships in advance, with the initial query.
HOW TO SPOT IT
Query count rising with the number of records displayed.
WHAT TO USE
A development tool showing queries per request.
