Databse indexing

I have multiple tables in my database and I want to do database indexing . So what are best practices ?
On which values shou;d I create index?

You should index the fields where You are searching for… That sounds obvious, but without schemas, it’s difficult to say more.

What about on foreign_keys?

The system usually takes care of indexing reference fields.

A concrete example would be a User name, a product title, an event date etc.

Use The Index, Luke

No, really, I can’t recommend this resource enough.