Jackie-Jiang commented on PR #14758:
URL: https://github.com/apache/pinot/pull/14758#issuecomment-2574352116
Will this rule prevent us from doing:
```
SELECT ... FROM t1 WHERE t1.col IN (SELECT t2.col FROM t2)
```
We don't always want to pay overhead of distinct when we already know the
value is unique, or there are very few duplicates.
Even without distinct, the result is still correct, just not necessary the
most efficient way to execute. For the example query, in order to achieve the
desired query plan, we can write it as:
```
SELECT
distinctCount(a.userUUID),
a.deviceOS
FROM userAttributes a WHERE a.userUUID IN
(
SELECT DISTINCT userUUID
FROM userGroups
WHERE groupUUID = 'group-1'
)
GROUP BY a.deviceOS
```
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]