[
https://issues.apache.org/jira/browse/CALCITE-7093?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18007512#comment-18007512
]
Stamatis Zampetakis commented on CALCITE-7093:
----------------------------------------------
Hey [~mbudiu], can you elaborate a bit why we need a rule based configuration
to change the cost-model and it is not sufficient to switch the metadata
provider for {{BuiltInMetadata.CumulativeCost}}?
> DPhyp algorithm should accept cost model as parameter
> -----------------------------------------------------
>
> Key: CALCITE-7093
> URL: https://issues.apache.org/jira/browse/CALCITE-7093
> Project: Calcite
> Issue Type: Wish
> Components: core
> Affects Versions: 1.40.0
> Reporter: Mihai Budiu
> Priority: Minor
>
> This is about the hypergraph-based optimization introduced in [CALCITE-6846]
> by [~dongsl].
> The algorithm makes calls to a cost model using getCumulativeCost() (function
> chooseBetterPlan()); the cost model is obtained from the Rel nodes.
> It could be useful to allow add to the the rule configuration an API to
> specify a cost model, similar to the MULTI_JOIN_OPTIMIZE rule
> (LoptOptimizeJoinRule), whose Config has as "withCostFunction" api.
> For example, this would allow the algorithm to emulate bushy join
> optimization using a cost model that optimizes for plan depth.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)