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Getting the most out of your database

Under conventional wisdom, pruning can only be achieved when querying by the partition key. However, if your data follows certain patterns, using some clever tricks you can achieve pruning even when filtering by non-partition key columns.

You execute a query that joins two tables with a valid an enforces foreign key and it returns no results. How is it possible? We thought it wasn't possible, but a recent incident revealed an edge case we never thought about. In this article I show how und

When it comes to database optimization, developers often reach for the same old tools: rewrite the query slightly differently, slap an index on a column, denormalize, analyze, vacuum, cluster, repeat. Conventional techniques are effective, but sometimes b

Django signals are extremely useful for decoupling modules and implementing complicated workflows. However, the underlying transport for signals makes them unreliable and subject to unexpected failures.In this article, I present an alternative transport i

Constraints keep the integrity of your system and prevent you from shooting yourself in the foot. Foreign keys are a special type of constraint because, unlike unique, check, and primary keys, they span more than one relation. This makes foreign keys hard

"Get or create" is a very common operation for syncing data in the database, but implementing it correctly may be trickier than you may expect. If you ever had to implement it in a real system with real-life load, you may have overlooked potential race co

I'm fairly sure that Excel is the most common way to store data, manipulate data, and yes(!), even pass data around. This is why it's not uncommon to find yourself reading Excel in Python. In this article I compare several ways to read Excel from Python.

How outliers can trick the optimizer into the wrong plan

3 interesting uses of DISTINCT in PostgreSQL