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https://issues.apache.org/jira/browse/CALCITE-3769?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17048454#comment-17048454
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Danny Chen commented on CALCITE-3769:
-------------------------------------
The EnumerableTableScan can not handle projects/filter expressions push down
correctly, but the BindableTableScan did, see [1], also if the table is a
ScannableTable, it expects to bind the data from the DataContext directly,
there is no need for code generation ~
As the default, we set the CalciteSystemProperty.ENABLE_ENUMERABLE as true, but
exclude the bindable rules, we added a EnumerableInterpreterRule.INSTANCE to
convert a bindable table scan to ENUMERABLE convention.
In Calcite, the logic does not change for these tables before/after this patch,
[~eolivelli] has a plan diff because they have a FilterableTable witch a
EnumerableTableScan impl, which is actually wrong.
[1]
https://github.com/apache/calcite/blob/eab156a88baf992644fc7b185dc7c730a49154f7/core/src/main/java/org/apache/calcite/interpreter/Bindables.java#L185
> Deprecate TableScanRule
> -----------------------
>
> Key: CALCITE-3769
> URL: https://issues.apache.org/jira/browse/CALCITE-3769
> Project: Calcite
> Issue Type: Wish
> Components: core
> Affects Versions: 1.21.0
> Reporter: Danny Chen
> Assignee: Danny Chen
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.22.0
>
> Time Spent: 1h 20m
> Remaining Estimate: 0h
>
> The TableScanRule is the only planner rule that for a logical node(e.g. the
> table scan), its function is to pass along the cluster object and invoke the
> RelOptTable#toRel which is very trivial because it supplies only a simple
> ToRelContext that does not support expanding view/passing table hints.
> For rels that come from the sql-to-rel conversion, there is already a table
> conversion logic[1]. This code gives a more powerful ToRelContext that has
> the complete functionality.
> The only reason that I saw the meaning of existing TableScanRule is for the
> TableScan that comes from the RelBuilder#scan.
> So I would suggest to deprecate the TableScanRule, instead, we support
> translating the table directly in RelBuilder#scan,
> -We also add a new interface RelBuilder#scan(Iterable<String> tableNames,
> ToRelContext context), so that user can pass in a more powerful ToRelContext
> explicitly.- User can customize a TableScanFactory in the RelBuilder to do
> this.
> [1]
> https://github.com/apache/calcite/blob/d6fa25cd11625ad7b4b74dafbd0211c701b38d49/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java#L3498
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