You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues-all@impala.apache.org by "Zoltán Borók-Nagy (Jira)" <ji...@apache.org> on 2022/03/08 15:17:00 UTC

[jira] [Updated] (IMPALA-11168) Add pseudo-columns for Impala

     [ https://issues.apache.org/jira/browse/IMPALA-11168?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Zoltán Borók-Nagy updated IMPALA-11168:
---------------------------------------
    Description: 
Hive Supports a few pseudo-column (virtual column):
https://cwiki.apache.org/confluence/display/hive/languagemanual+virtualcolumns

It would be useful to add support for a few pseudo-columns for Impala as well.
E.g. to implement support for Iceberg position-based deletes we'd need the file name and ordinal position for each row.

Hive has {{INPUT_\_FILE_\_NAME}} which returns full URI of the data file. Unfortunately it doesn't have a pseudo-column for the ordinal position of rows. So we need to introduce a new pseudo-column for that, probably with the name {{ORDINAL_\_POSITION_\_INSIDE_\_FILE}}, or stg. like that.

  was:
Hive Supports a few pseudo-column (virtual column):
https://cwiki.apache.org/confluence/display/hive/languagemanual+virtualcolumns

It would be useful to add support for a few pseudo-columns for Impala as well.
E.g. to implement support for Iceberg position-based deletes we'd need the file name and ordinal position for each row.

Hive has {{INPUT__FILE__NAME}} which returns full URI of the data file. Unfortunately it doesn't have a pseudo-column for the ordinal position of rows. So we need to introduce a new pseudo-column for that, probably with the name {{ORDINAL__POSITION__INSIDE__FILE}}, or stg. like that.


> Add pseudo-columns for Impala
> -----------------------------
>
>                 Key: IMPALA-11168
>                 URL: https://issues.apache.org/jira/browse/IMPALA-11168
>             Project: IMPALA
>          Issue Type: New Feature
>          Components: Backend, Frontend
>            Reporter: Zoltán Borók-Nagy
>            Priority: Major
>
> Hive Supports a few pseudo-column (virtual column):
> https://cwiki.apache.org/confluence/display/hive/languagemanual+virtualcolumns
> It would be useful to add support for a few pseudo-columns for Impala as well.
> E.g. to implement support for Iceberg position-based deletes we'd need the file name and ordinal position for each row.
> Hive has {{INPUT_\_FILE_\_NAME}} which returns full URI of the data file. Unfortunately it doesn't have a pseudo-column for the ordinal position of rows. So we need to introduce a new pseudo-column for that, probably with the name {{ORDINAL_\_POSITION_\_INSIDE_\_FILE}}, or stg. like that.



--
This message was sent by Atlassian Jira
(v8.20.1#820001)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org