PRQL
Feature request: optimizer hints
What's up?
As far as I understand, optimizer hints are not supported.
I'm particularly interested to MariaDB / MySQL syntax:
< FROM | JOIN > <table_name> [ AS <alias >] < FORCE | USE | IGNORE > INDEX (< index_list >)
But any type of hint should be supported somehow.
Yes, interesting idea.
My sense is that these are mainly in transactional DBs — i.e. are less prevalent in DuckDB / BigQuery / Snowflake — and fairly DB-specific.
If that's correct, I'd think they'd be less of a focus for PRQL, though they could always be supplied within an S-String...
@max-sixty Yes, the syntax is purely for row-based databases and 100% specific to each database. And I understand your will to keep things standard. However, when indexes aren't used, a query might be completely unusable.
Based on the documentation, I don't understand how to insert s-strings in that position (after a table name). Would you please provide an example, and perhaps document it? Thank you!
It would be something like:
from s"SELECT first_name, id, age FROM employees FORCE foo bar"
...
...where FORCE foo bar is the optimizer hint — does that make sense? (Obv prql isn't that helpful in that specific query, it's intended to show the escape hatch...)