[
https://issues.apache.org/jira/browse/PHOENIX-1987?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14583762#comment-14583762
]
Shuxiong Ye commented on PHOENIX-1987:
--------------------------------------
I've done some experiment in mysql.
We have a table, which has one column and two rows, 1.0 and -1.0.
--------
| 1.0 |
| -1.0 |
--------
When we apply SQRT function for these two rows, we get result:
--------
| 1.0 |
| NULL |
--------
So I think when mysql encounters NaN, it turns it into NULL.
--------------------------------------------------------------
What's NULL in Numeric Type in Phoenix? Is it 0-length byte array?
> SIGN built-in function should be order preserving
> -------------------------------------------------
>
> Key: PHOENIX-1987
> URL: https://issues.apache.org/jira/browse/PHOENIX-1987
> Project: Phoenix
> Issue Type: Sub-task
> Reporter: James Taylor
> Assignee: Shuxiong Ye
> Fix For: 5.0.0, 4.5.0, 4.4.1
>
> Attachments:
> 0001-PHOENIX-1987-SIGN-built-in-function-should-be-order_v2.patch,
> 0001-PHOENIX-1987-fixing-getKeyFormationTraversalIndex-in-SIGN-function.patch
>
>
> The SIGN built-in function preserves the order of its input. This needs to be
> explicitly implemented in SignFunction by implementing the following method:
> {code}
> public OrderPreserving preservesOrder() {
> return OrderPreserving.YES;
> }
> {code}
> This will allow certain optimizations reducing the amount of memory and/or
> buffering that is required if SIGN is used in a GROUP BY or ORDER BY clause.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
