Fix assert failure for range window functions #14168
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Fixes rapidsai#13855. This commit fixes an erroneous assert check in range window functions, where the wrong data-type is checked for timestamp order-by columns. For timestamps, it's the duration::rep type that should be checked, when accessing the order by column. This fix allows ROLLING_TEST to complete correctly, in DEBUG mode.
| // For timestamp types, T must match the range rep type for the order-by column. | ||
| cudf_assert((type_id_matches_device_storage_type<T>(col.type().id()) or | ||
| cudf::type_dispatcher(col.type(), is_correct_range_rep{})) && | ||
| "data type mismatch when accessing the order-by column"); |
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I'm not sure I agree with retrieving the data (via element()) using the rep-type and doing operations on said rep-type. I would rather the actual type be read (via element()) and used directly.
I feel the original error is correct and this is a flaw in the design of this code perhaps.
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The reason we're comparing the rep-type values here is that the order-by columns are timestamps, and the preceding/following values are durations (e.g. 2 days ago).
For integral order-by columns, preceding/following are of the same types. But not for timestamps.
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Hmm. That said, maybe I could stand to tighten this up a little more... I'll see about a stricter check for timestamps.
I did take a look. By this point, the duration types for preceding and following are normalized with the order-by's timestamp types already, upstream.
For this release, I'd rather we didn't dismantle the logic in range_window_bounds (i.e. using rep-types) as part of fixing this assert condition. I could tackle this as a follow-on, if that's agreeable.
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Ah, I just realized that one unintended consequence of doing order-by comparisons without switching to the rep-types is that all those templates will be instantiated for all timestamp types, duration types, fixed-point, etc. :/
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/ok to test |
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/ok to test |
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/merge |
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This change has been merged. Thank you all for the reviews. |
Fixes #13855.
This commit fixes an erroneous assert check in range window functions, where the wrong data-type is checked for timestamp order-by columns.
For timestamps, it's the
duration::reptype that should be checked, when accessing the order by column.This fix allows ROLLING_TEST to complete correctly, in DEBUG mode.
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