[jira] [Updated] (OPTIQ-302) Use heuristic rule to plan queries with large numbers of joins

["Julian Hyde (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/OPTIQ-302?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Julian Hyde updated OPTIQ-302:
------------------------------

    Fix Version/s: 0.8

> Use heuristic rule to plan queries with large numbers of joins
> --------------------------------------------------------------
>
>                 Key: OPTIQ-302
>                 URL: https://issues.apache.org/jira/browse/OPTIQ-302
>             Project: Optiq
>          Issue Type: Bug
>            Reporter: GitHub Import
>              Labels: github-import
>             Fix For: 0.8
>
>
> If a query has a large number of joins, the planning time and space grows exponentially in N, the number of joins. About about N=8 it is not possible to plan a query exhaustively.
> `LoptOptimizeJoinRule` is a heuristic join rule that uses a greedy algorithm. It operates on a `MultiJoinRel`, which must first have been created using `ConvertMultiJoinRule`. Enabling this rule, and disable the join transformation rules `SwapJoinRule` and `PushJoinThroughJoinRule`, it is possible to plan queries with N=60 and higher.
> ---------------- Imported from GitHub ----------------
> Url: https://github.com/julianhyde/optiq/issues/302
> Created by: [julianhyde|https://github.com/julianhyde]
> Labels: 
> Created at: Wed Jun 18 03:27:16 CEST 2014
> State: open



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