docs: Clarify first_value usage in select vs aggregate#1348
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AdMub wants to merge 2 commits intoapache:mainfrom
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docs: Clarify first_value usage in select vs aggregate#1348AdMub wants to merge 2 commits intoapache:mainfrom
AdMub wants to merge 2 commits intoapache:mainfrom
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Clarifies that aggregate functions like first_value must be used within .aggregate() and not .select(). Closes apache#1300.
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nuno-faria
requested changes
Feb 8, 2026
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| def last_value( |
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Should the same type of clarification be done on last_value as well?
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| For example:: | ||
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| df.select(first_value(col("a"), order_by="ts")) |
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This example also needs to be changed right?
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| For example:: | ||
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| df.select(last_value(col("a"), order_by="ts")) |
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Similar example as the first_value one.
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I investigated Issue #1300 and confirmed that the crash occurs because first_value (an aggregate function) is used inside .select(), which is not supported by the physical planner. This PR updates the docstring to explicitly warn users that first_value should be used with .aggregate() and not .select(). Closes #1300.