SQL: Ability to generate exact distinct count queries. #3999
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
gianm
force-pushed
the
sql-exact-count-distinct
branch
from
a2bdd0c
to
11897c5
Compare
|
👍 |
nishantmonu51
approved these changes
Mar 3, 2017
| @@ -122,6 +122,14 @@ public int getMaxTopNLimit() | |||
| return 0; | |||
| } | |||
| }; | |||
| private static final PlannerConfig PLANNER_CONFIG_NO_HLL = new PlannerConfig() | |||
There was a problem hiding this comment.
minor nit: rename to PLANNER_CONFIG_NO_APPROXIMATION ?
There was a problem hiding this comment.
There's also PLANNER_CONFIG_NO_TOPN to disable topn approximations, so I want to keep them different for that reason.
There was a problem hiding this comment.
The two kinds of approximations can be toggled separately
|
I'm going to make one tweak to the wording, please don't merge just yet |
|
Haha, oops. I'll do another PR |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Uses Calcite's AggregateExpandDistinctAggregatesRule to generate exact distinct count queries when useApproximateCountDistinct is "false". These query plans use nested groupBys.