[
https://issues.apache.org/jira/browse/CALCITE-1588?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16107708#comment-16107708
]
Julian Hyde commented on CALCITE-1588:
--------------------------------------
[~gian], That's OK. If we're going to add an on-off switch (allow
approximation) we might as well add a control knob as well. If people ask Druid
for accuracy of 0.01% then they are going to get slow exact distinct count, or
an error saying the system can't answer their query. Which is fine.
> Add SQL syntax to allow approximate LIMIT and distinct-COUNT
> ------------------------------------------------------------
>
> Key: CALCITE-1588
> URL: https://issues.apache.org/jira/browse/CALCITE-1588
> Project: Calcite
> Issue Type: Bug
> Reporter: Julian Hyde
> Assignee: Julian Hyde
>
> Add SQL syntax to allow approximate LIMIT and distinct-COUNT. These will set
> the properties specified in CALCITE-1587. By default the properties are
> false, so the query will return exact results.
> Exact syntax is to be decided. It could be at the top of the query (therefore
> affecting every LIMIT or aggregate in the query) or it could be more
> localized (e.g. {{COUNT(DISTINCT customerId) APPROXIMATE (WITHIN 10
> PERCENT)}}).
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
