[jira] [Commented] (PHOENIX-6433) DISCUSS: Disllow creating new tables with duplicate column qualifiers by default.

["Istvan Toth (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/PHOENIX-6433?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17315267#comment-17315267 ] 

Istvan Toth commented on PHOENIX-6433:
--------------------------------------

Considering that we need some kind of override for testing, (3) seems to be the best solution to me. 
We only need to check the option on table creation, so it shouldn't cause performance issues.
Also IMO the default should be disallowing.


> DISCUSS: Disllow creating new tables with duplicate column qualifiers by default.
> ---------------------------------------------------------------------------------
>
>                 Key: PHOENIX-6433
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-6433
>             Project: Phoenix
>          Issue Type: Wish
>            Reporter: Lars Hofhansl
>            Priority: Major
>
> Phoenix allows specifying columns to "reside" in specific column families. As long as the columns are unique you can simply refer to them via the column name. In that case the column families are just about the physical placement of the columns. No special SQL constructs are needed... This is similar to indexes, they are for optimization, but queries are unchanged.
> However...
> Currently Phoenix also allows creating tables with duplicate column qualifiers such as:
> {{CREATE TABLE t (pk1 ..., x.v1, y.v1, ...)}} or
> {{CREATE TABLE t (pk1 ..., v1, x.v1, ...)}}
> In the first case you must specific any reference to {{v1}} with the column family or an {{AmbiguousColumnException}} is thrown. In the second case {{v1}} refers to the {{0.v1}}.
> In both cases the physical optimization of the column storage now leaks into the SQL queries - unnecessarily, IMHO at least.
> For tables not created in Phoenix, or with dynamic columns, this is not avoidable. 
> I do think we should disallow creating new tables with duplicated (static) column names, to reduce confusion and surprises.
> Related: PHOENIX-6343



--
This message was sent by Atlassian Jira
(v8.3.4#803005)