private final Map<ObjectIdentifier, FunctionDefintion> tempFunctions = new LinkedHashMap<>();

Status

Current state: Under Discussion

Discussion thread: http://apache-flink-mailing-list-archive.1008284.n3.nabble.com/DISCUSS-FLIP-57-Rework-FunctionCatalog-td32291.html#a32613

JIRA: FLINK-14090

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Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

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This FLIP would add explicit temporary function support by renaming a few variable names, and potential deprecating renaming some APIs in favor of new APIs that reflects their nature of dealing with temporary functions.

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Their DDLs are “CREATE/DROP TEMPORARY SYSTEM FUNCTION”.

Existing They will be renamed from “registerScalar/Table/AggregateFunctions()” will be deprecated in favor of the new APIs.

b) Temporary Catalog Functions

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Class FunctionIdentifier {
    // for temporary/non-temporary system function

    // for temporary/non-temporary catalog function
	ObjectIdentifier oi;

    Optional<ObjectIdentifier> getIdentifier() {}
    Optional<String> getSimpleName( getName() {}

    Optional<FunctionIdentifier> of(ObjectIdentifier oi) {}
    Optional<FunctionIdentifier> of(String name) {}
    
}

Changes to CallExpression and UnresolvedCallExpression

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