MySQL 8.0

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CREATE TABLE `Grouping`
    (`GroupingKey` varchar(8), `GroupingValue` varchar(7), `GroupingType` varchar(8));

INSERT INTO `Grouping`
    (`GroupingKey`, `GroupingValue`, `GroupingType`)
VALUES
    ('Language', 'Italian', 'Category'),
    ('Language', 'Russian', 'Unknown'),
    ('Unknown', 'Unknown', 'Unknown'),
    ('Phone', 'Unknown', 'Unknown');
SELECT * FROM `Grouping`
WHERE NOT (
            groupingkey = 'Unknown'
        AND groupingvalue = 'Unknown'
        AND groupingtype = 'Unknown'
          )


GroupingKey
GroupingValue
GroupingType


Language
Italian
Category

Language
Russian
Unknown

Phone
Unknown
Unknown


SELECT * FROM `Grouping`
WHERE (groupingkey, groupingvalue, groupingtype) <> ('Unknown', 'Unknown', 'Unknown')


GroupingKey
GroupingValue
GroupingType


Language
Italian
Category

Language
Russian
Unknown

Phone
Unknown
Unknown


SELECT * FROM `Grouping`
WHERE groupingkey <> 'Unknown'
   OR groupingvalue <> 'Unknown'
   OR groupingtype <> 'Unknown'


GroupingKey
GroupingValue
GroupingType


Language
Italian
Category

Language
Russian
Unknown

Phone
Unknown
Unknown

GroupingKey	GroupingValue	GroupingType
Language	Italian	Category
Language	Russian	Unknown
Phone	Unknown	Unknown