[jira] [Commented] (PARQUET-2034) Document dictionary page position

["ASF GitHub Bot (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/PARQUET-2034?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17367186#comment-17367186 ] 

ASF GitHub Bot commented on PARQUET-2034:
-----------------------------------------

gszadovszky opened a new pull request #177:
URL: https://github.com/apache/parquet-format/pull/177


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> Document dictionary page position
> ---------------------------------
>
>                 Key: PARQUET-2034
>                 URL: https://issues.apache.org/jira/browse/PARQUET-2034
>             Project: Parquet
>          Issue Type: Bug
>          Components: parquet-format
>            Reporter: Gabor Szadovszky
>            Priority: Major
>
> Dictionary page shall be always written to the first position of the column chunk. Unfortunately, we only have one statement about this "hidden" at the [encodings doc|https://github.com/apache/parquet-format/blob/master/Encodings.md#dictionary-encoding-plain_dictionary--2-and-rle_dictionary--8]:
> {quote}The dictionary page is written first, before the data pages of the column chunk.{quote}
> This statement is not emphasized enough and not prepared for the potential extension of the available page types. It also should be placed to a more central place of the specification and also in the thrift file.



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