Function registerNullableGroupByKeys

src/Analyzer/Resolve/QueryAnalyzer.cpp:3839–3871

Register GROUP BY keys in scope.nullable_group_by_keys in every shape in which an expression * equal to a key can arrive at the lookup in resolveExpressionNode, so that the lookup can use * exact comparison (including types): * - the original form, for keys resolved from scratch; * - the form with every maximal proper sub-key already converted to Nullable and the types of * the nodes a

  * All shapes are mapped to the original key node.
  */
void registerNullableGroupByKeys(const QueryTreeNodes & group_by_keys, IdentifierResolveScope & scope)
{
    for (const auto & key : group_by_keys)
        scope.nullable_group_by_keys.emplace(key, key);

    for (const auto & key : group_by_keys)
    {
        if (key->as<FunctionNode>())
        {
            auto key_with_converted_sub_keys = key->clone();
            bool converted = false;

            for (auto & child : key_with_converted_sub_keys->getChildren())
            {
                if (child && convertNestedGroupByKeysToNullable(child, scope.nullable_group_by_keys, scope.context))
                    converted = true;
            }

            if (converted)
            {
                rerunFunctionResolve(key_with_converted_sub_keys->as<FunctionNode>(), scope.context);
                scope.nullable_group_by_keys.emplace(std::move(key_with_converted_sub_keys), key);
            }
        }

        if (nodeSupportsConvertToNullable(key))
        {
            auto converted_key = key->clone();
            converted_key->convertToNullable();
            scope.nullable_group_by_keys.emplace(std::move(converted_key), key);
        }
    }
}

}