[
https://issues.apache.org/jira/browse/CALCITE-497?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14270034#comment-14270034
]
Julian Hyde commented on CALCITE-497:
-------------------------------------
> What happens if a field is not unique among records and you try to reference
> it by it's name?
If it's not unique at a given depth, it will find neither. I will say 'column v
not found' or similar.
> What about the case in which there's a column name that conflicts with the
> record field name, like this?
If it's unique at a given depth Calcite will not look deeper. So, {{select k
from T}} will use k, not a.k.
Sounds like this is inconsistent with Phoenix. But I didn't want to bake in a 2
level scheme, where records (column families) are inferior to columns.
> Support optional qualifier for column name references
> -----------------------------------------------------
>
> Key: CALCITE-497
> URL: https://issues.apache.org/jira/browse/CALCITE-497
> Project: Calcite
> Issue Type: Sub-task
> Reporter: James Taylor
> Assignee: Julian Hyde
> Labels: phoenix
> Fix For: 1.0.0-incubating
>
>
> Some systems, such as HBase, have a named group to which columns belong (i.e.
> a column family in this case). To disambiguate column references (i.e. if the
> same column name is used in different column families), it's useful to allow
> an optional qualifier. This is similar to the RECORD field mechanism that
> Calcite already supports, but in this case the record name would be optional,
> since it's not necessary if the column names are unique. For example:
> http://phoenix.apache.org/language/index.html#column_ref
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
