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Ruby Active Record Associations in Rails Active Record Associations Has Many Associations

Kyle Case
Kyle Case
44,857 Points
Posted by Kyle Case
Kyle Case
44,857 Points

Adding an Index

Is there rule of thumb for when an index is/isn't needed. Should every foreign key column have an index added to it?

1 Answer

Jay McGavren
STAFF
Jay McGavren
Treehouse Teacher
Jay McGavren
Jay McGavren
Treehouse Teacher

I'm reluctant to talk in absolutes, but I'm not aware of any cases where you wouldn't want an index on a foreign key.

Here's a Stack Overflow discussion about indexes.