[jira] [Assigned] (CALCITE-6885) SqlToRelConverter#convertUsing should not fail if commonTypeForBinaryComparison returns null

["Ruben Q L (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/CALCITE-6885?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Ruben Q L reassigned CALCITE-6885:
----------------------------------

    Assignee: Ruben Q L

> SqlToRelConverter#convertUsing should not fail if commonTypeForBinaryComparison returns null
> --------------------------------------------------------------------------------------------
>
>                 Key: CALCITE-6885
>                 URL: https://issues.apache.org/jira/browse/CALCITE-6885
>             Project: Calcite
>          Issue Type: Bug
>          Components: core
>            Reporter: Ruben Q L
>            Assignee: Ruben Q L
>            Priority: Blocker
>              Labels: pull-request-available
>             Fix For: 1.39.0
>
>
> CALCITE-6413 introduced the following code in {{SqlToRelConverter#convertUsing}} :
> {code}
> RelDataType resultType =
>   validator().getTypeCoercion().commonTypeForBinaryComparison(
>     comparedTypes.get(0), comparedTypes.get(1));
> if (resultType == null) {
>   // This should never happen, since the program has been validated.
>   throw new IllegalArgumentException("Cannot join on field `" + name
>     + "` because the types are not comparable: " + comparedTypes);
> }
> {code}
> This can cause regressions on downstream projects which use their own TypeCoercion, and which decide to return {{null}} in some circumstances, e.g. to avoid forcing any coercion from Calcite planner side, and leave the original expression as it is because they rely on a runtime engine coercion (outside of Calcite scope).
> Notice that the above code (to convert Join's using condition) is NOT aligned with code for binary call expressions, as we can see here:
> https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/sql/validate/implicit/TypeCoercionImpl.java#L244
> If the commonTypeForBinaryComparison returns null, then the binary call is left untouched (no coercion), and the process goes on, without any exception.
> {{SqlToRelConverter#convertUsing}} should probably behave in the same way to avoid any regression, i.e.:
> {code}
> RelDataType resultType =
>   validator().getTypeCoercion().commonTypeForBinaryComparison(
>     comparedTypes.get(0), comparedTypes.get(1));
> if (resultType == null) {
>   // keep old code, no expcetion
>   list.add(rexBuilder.makeCall(SqlStdOperatorTable.EQUALS, operands));
> } else {
>   // new code from CALCITE-6413
>   List<RexNode> castedOperands = new ArrayList<>();
>   ...
>   list.add(rexBuilder.makeCall(SqlStdOperatorTable.EQUALS, 
> }
> {code}



--
This message was sent by Atlassian Jira
(v8.20.10#820010)