[MySQL] 同じカラム合計値を複数条件で別々に

SELECT SUM(CASE WHEN Jouhou = 'A' THEN 1 ELSE 0 END)as 'A',
       SUM(CASE WHEN Jouhou = 'B' THEN 1 ELSE 0 END)as 'B',
       SUM(CASE WHEN Jouhou IS NULL THEN 1 ELSE 0 END)as 'null'
FROM   DBTable
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