Comonut opened a new pull request #29424:
URL: https://github.com/apache/spark/pull/29424
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### What changes were proposed in this pull request?
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In the docs concerning the approx_count_distinct I have changed the
description of the rsd parameter from **_maximum estimation error allowed_** to
_**maximum relative standard deviation allowed**_
### Why are the changes needed?
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Maximum estimation error allowed can be misleading. You can set the target
relative standard deviation, which affects the estimation error, but on given
runs the estimation error can still be above the rsd parameter.
### Does this PR introduce _any_ user-facing change?
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This PR should make it easier for users reading the docs to understand that
the rsd parameter in approx_count_distinct doesn't cap the estimation error,
but just sets the target deviation instead,
### How was this patch tested?
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No tests, as no code changes were made.
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