fix(mssql): restore unbounded window functions #8411
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MSSQL requires an order-by clause in unbounded windows. The behavior of the mssql sqlalchemy connector is to order by the field used in the window function. This seems silly, and potentially slightly computationally wasteful, but not incorrect.
cpcloud
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Feb 21, 2024
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Description of changes
MSSQL requires an order-by clause in unbounded windows. This is clearly
documented in
https://learn.microsoft.com/en-us/sql/relational-databases/errors-events/database-engine-events-and-errors-10000-to-10999
(just kidding, it's a huge list of error codes you have to scroll through. You
want Error 10756)
The behavior of the mssql sqlalchemy connector is to order by the field used in
the window function. This seems silly, and potentially slightly
computationally wasteful, but not incorrect.
So, I've added a rewrite rule to the MSSQL compiler that copies this behavior
for all reduction functions that aren't UDFs, since those aren't supported
anyway (and would require a different rewrite rule, in any case).
Issues closed