MySQL GroupBy и го показва хоризонтално

Опитайте това,

SELECT  VendorID,
        SUM(CASE WHEN Score = 'A' THEN 1 ELSE 0 END) totalA,
        SUM(CASE WHEN Score = 'B' THEN 1 ELSE 0 END) totalB,
        SUM(CASE WHEN Score = 'C' THEN 1 ELSE 0 END) totalC
FROM    tableName
GROUP BY VendorID

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