Fix Pre Process Metadata Call when facing CTE Issue

[konjac-h]

Description

When handling the query below with Common Table Expression (CTE)

WITH temp_cte AS (
    SELECT *
    FROM tpch.tiny.orders
)
SELECT *
FROM temp_cte

If a QuerySpecification node has the Optional from, Visitor will visit the corresponding table (visitTable). Subsequently, MetadataExtractor will include the table in its list of tableNames and then call 1getTableColumnMetadata`.

It will lead to unnecessary invocations of getTableColumnMetadata and getTableHandle when a query has a Common Table Expression (CTE).

To fix this issue, we will need to determine if the table_name inside query from <table_name> is from the CTE expression. If yes, we need to exclude it without sending request to getTableColumnMetadata

Impact

Fixing the pre_process_meatdata calls. It will help us reduce a lot of unnecessary call to getTableColumnMetadata and latency.

Test Plan

• Testing locally
• Verifier Test
• I have ran the query that had the issue with prev version but got it fixed now with pre_process_metadata_calls enabled

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• PR description addresses the issue accurately and concisely. If the change is non-trivial, a GitHub Issue is referenced.
• Documented new properties (with its default value), SQL syntax, functions, or other functionality.
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• Adequate tests were added if applicable.
• CI passed.

[jaystarshot]

Will it work if you pass analysis to the metadataExtractor call and then use the analysis to determine this like done in RelationPlanner here

[jaystarshot]

Also is there a way to add tests?

[jainxrohit]

Instead of calling it add addCTE, can we come up with some type agnostic name, such as skipProcessing(identifier)

[jainxrohit]

Similar to below comment, this could be generalized by checking context.shouldSkipProcessing(identifier)?

[konjac-h]

sounds good

[jainxrohit]

is there a way to add tests?

+1, Lets add tests for with clause handling.

[konjac-h]

Also is there a way to add tests?

Yea, I'm trying to figure out a valid test case which can fetch the corresponding Runtimestats info to help us verify it

[jainxrohit]

Move the comment to top line

[konjac-h]

done, thanks

[NikhilCollooru]

LGTM

[konjac-h]

thanks nikhil for helping merge it!

[yingsu00]

@konjac-h Is there notable performance improvement to CTE selections? If yes, can you please provide a release note? Does the following sound good?

Improve the performance of reading common table expressions (CTE).