sqllogictest VS citus

That specific SQLite test suite (one of four [1]) has loads of generated SQL functions, and a long tail of more complex hand-written tests. That 95% of the test suite will be mostly generated queries that follow the same basic pattern of joins and projections with basic arithmetic and comparisons. See for example [2] and [3].

The generated tests are not designed to test a wide breadth of features of the SQL language, and passing them with a simple engine is very doable. A lot of the value of these tests is that the sheer volume of queries tends to find obscure problems in optimizers that would not easily surface otherwise. That is of course not a problem in a simple engine that does not have an optimizer.

[1] https://www.sqlite.org/testing.html#test_harnesses

[2] https://github.com/gregrahn/sqllogictest/blob/master/test/ra...

[3] https://raw.githubusercontent.com/gregrahn/sqllogictest/mast...

I see they don't mention Citus (https://github.com/citusdata/citus), which is already a fairly mature native Postgres extension. From the details given in the article, in sounds like they just reimplemented it.

I wonder if they were unaware of it or disregarded it for a reason —I currently am in a similar situation as the one described in the blog, trying to shard a massive Postgres DB.

It is possible, if you pay for it. You can do Multi-AZ Clustered Instances in RDS, where you get the benefits of Multi-AZ failover with traffic sharing.

If you can run your own infra – at least on an EC2 level – you can do things like Citus [0] for Postgres, which is about as close to "just add database nodes" as you'll get.

[0]: https://www.citusdata.com/

So while searching for something like this for postgres I came across citus. Any one know how that stacks up?

https://github.com/citusdata/citus

References: CitusDB