Danny Chen created CALCITE-3769:
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             Summary: 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
             Fix For: 1.22.0


The TableScanRule is the only planner rule that for a logical node(e.g. the 
table scan), it’s functionality is to pass along the cluster object and invoke 
the RelOptTable#toRel. It’s function is very trivial because it supplies only a 
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 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 we can pass in a more powerful ToRelContext 
explicitly.

[1] 
https://github.com/apache/calcite/blob/d6fa25cd11625ad7b4b74dafbd0211c701b38d49/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java#L3498



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