How it works Skills Methodology Pricing Sign In / Up

Practice/Beyond the Path: Pipelines, Modeling & Performance

SQL pattern

Query performance & plans

7 problems in this pattern, climbing easy → medium → hard. Pick wherever you're calibrated.

Easy

0 / 2 solved

Filter one day of timestamps without wrapping the column
SQL · ~8 min
NEW
Find who full-scans partitioned tables
SQL · ~10 min
NEW

Medium

0 / 3 solved

Prune partitions for a window that crosses midnight
SQL · ~12 min
NEW
Fetch the next page with a keyset cursor
SQL · ~12 min
NEW
Find the join keys that would skew a shuffle
SQL · ~12 min
NEW

Hard

0 / 2 solved

Find where a plan's row estimate goes wrong
SQL · ~20 min
NEW
Flag queries that got at least twice as slow
SQL · ~18 min
NEW