You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@hive.apache.org by Gabriel Balan <ga...@oracle.com> on 2020/11/06 10:55:47 UTC
what does MM stand for
Hello
Apologies for the silly question.
What you say "MM tables", what does MM stand for?
> HIVE_MM_ALLOW_ORIGINALS("hive.mm.allow.originals", false,
> "Whether to allow original files in MM tables. Conversion to MM may be expensive if\n" +
> "this is set to false, however unless MAPREDUCE-7086 fix is present (hadoop 3.1.1+),\n" +
> "queries that read non-orc *MM tables* with original files will fail. The default in\n" +
> "Hive 3.0 is false."),
thank you
Gabriel Balan
P.S. And since I'm already showing my ignorance, I've also seen these mentioned:
* DP tables <https://issues.apache.org/jira/secure/attachment/12833236/HIVE-14643.patch> (dynamic partitions?)
* SMB table <https://issues.apache.org/jira/browse/HIVE-20620> (sort merge bucket?)
--
The statements and opinions expressed here are my own and do not necessarily represent those of Oracle Corporation.
Re: what does MM stand for
Posted by Mich Talebzadeh <mi...@gmail.com>.
MM -> Micro Managed
Hive managed tables supporting Insert-only operations with ACID semantics
are called MM (Micro-Managed) OR Insert-Only ACID tables. Supports all file
formats.
From say
https://docs.cloudera.com/HDPDocuments/DLM1/DLM-1.5.1/administration/content/dlm_acid_tables_replication.html
HTH
LinkedIn * https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw
<https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw>*
*Disclaimer:* Use it at your own risk. Any and all responsibility for any
loss, damage or destruction of data or any other property which may arise
from relying on this email's technical content is explicitly disclaimed.
The author will in no case be liable for any monetary damages arising from
such loss, damage or destruction.
On Fri, 6 Nov 2020 at 10:56, Gabriel Balan <ga...@oracle.com> wrote:
> Hello
>
> Apologies for the silly question.
>
> What you say "MM tables", what does MM stand for?
>
> HIVE_MM_ALLOW_ORIGINALS("hive.mm.allow.originals", false,
> "Whether to allow original files in MM tables. Conversion to MM
> may be expensive if\n" +
> "this is set to false, however unless MAPREDUCE-7086 fix is
> present (hadoop 3.1.1+),\n" +
> "queries that read non-orc *MM tables* with original files will
> fail. The default in\n" +
> "Hive 3.0 is false."),
>
> thank you
>
> Gabriel Balan
>
> P.S. And since I'm already showing my ignorance, I've also seen these
> mentioned:
>
> - DP tables
> <https://issues.apache.org/jira/secure/attachment/12833236/HIVE-14643.patch>
> (dynamic partitions?)
> - SMB table <https://issues.apache.org/jira/browse/HIVE-20620> (sort
> merge bucket?)
>
>
>
> --
> The statements and opinions expressed here are my own and do not necessarily represent those of Oracle Corporation.
>
>