[Doc] Update the document of velox backend support functions

[xinghuayu007]

What changes were proposed in this pull request?

Update the document 'docs/velox-backend-support-progress.md' and clarify the supported functions.

(Fixes: #ISSUE-ID)

How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)

(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

[github-actions]

Thanks for opening a pull request!

Could you open an issue for this pull request on Github Issues?

https://github.com/apache/incubator-gluten/issues

Then could you also rename commit message and pull request title in the following format?

[GLUTEN-${ISSUES_ID}][COMPONENT]feat/fix: ${detailed message}

See also:

• Other pull requests

[marin-ma]

Thanks for working on this. However, we already have an issue #8821 to track the function support. #8822 is for this issue and the function support lists are automatically generated from an internal script. With this approach, we can regularly update the function support list without much manual maintenance in the future.

I will close this one and it's welcomed to review #8822 and the follow-up PRs. Thanks!

[marin-ma]

There are fallback logs

12:35:13.302 WARN org.apache.spark.sql.execution.GlutenFallbackReporter: Validation failed for plan: Project[QueryId=133], due to: 
 - Native validation failed: 
   |- Validation failed due to exception caught at file:SubstraitToVeloxPlanValidator.cc line:1368 function:validate, thrown from file:ExprCompiler.cpp line:475 function:compileRewrittenExpression, reason:Scalar function name not registered: array_union, called with arguments: (ARRAY<DOUBLE>, ARRAY<DOUBLE>).

Seems like array_union is not supported.

[marin-ma]

explode is supported, while explode_outer is not. This PR is working on it.

[marin-ma]

The return type for "make_interval" is CalendarIntervalType, which is not supported yet.

[marin-ma]

12:38:33.093 WARN org.apache.spark.sql.execution.GlutenFallbackReporter: Validation failed for plan: Project[QueryId=3888], due to: 
 - Native validation failed: 
   |- Validation failed at file:SubstraitToVeloxPlanValidator.cc, line:236, function:validateScalarFunction, reason:Function is not supported: from_json

[marin-ma]

12:37:58.806 WARN org.apache.spark.sql.execution.GlutenFallbackReporter: Validation failed for plan: Project[QueryId=3176], due to: 
 - Native validation failed: 
   |- Validation failed due to exception caught at file:SubstraitToVeloxPlanValidator.cc line:1368 function:validate, thrown from file:ExprCompiler.cpp line:475 function:compileRewrittenExpression, reason:Scalar function name not registered: to_json, called with arguments: (ROW<a:INTEGER,b:INTEGER>).

[marin-ma]

12:35:31.555 WARN org.apache.spark.sql.execution.GlutenFallbackReporter: Validation failed for plan: ObjectHashAggregate[QueryId=675], due to: 
 - Native validation failed: 
   |- Validation failed at file:SubstraitToVeloxPlanValidator.cc, line:1235, function:validate, reason:approx_percentile was not supported in AggregateRel.

[marin-ma]

12:35:41.114 WARN org.apache.spark.sql.execution.GlutenFallbackReporter: Validation failed for plan: Project[QueryId=985], due to: 
 - Native validation failed: 
   |- Validation failed due to exception caught at file:SubstraitToVeloxPlanValidator.cc line:1368 function:validate, thrown from file:ExprCompiler.cpp line:475 function:compileRewrittenExpression, reason:Scalar function name not registered: timestamp_seconds, called with arguments: (INTEGER).