Código SQL:
Ver original
SELECT modified_by, COUNT(modified_by) AS TotalReviewer, COUNT(t1.FilesInError) AS FilesInError FROM FileSubstatus LEFT JOIN( SELECT modified_by AS c2, COUNT(modified_by) AS FilesInError FROM FileSubstatus WHERE COL1 IN ('Error1') GROUP BY modified_by )t1 ON t1.c2=modified_by GROUP BY modified_by