CREATE TABLE member (Member_ID CLOB, Name CLOB, Nationality CLOB, Role CLOB)
CREATE TABLE performance (Performance_ID FLOAT, Date CLOB, Host CLOB, Location CLOB, Attendance NUMBER)
CREATE TABLE member_attendance (Member_ID NUMBER, Performance_ID NUMBER, Num_of_Pieces NUMBER)

A bar chart for showing the number of the dates of performances with attending members whose roles are 'Violin', and list by the Date in descending.
SELECT Date, COUNT(Date) FROM member_attendance AS T1 JOIN member AS T2 ON T1.Member_ID = T2.Member_ID JOIN performance AS T3 ON T1.Performance_ID = T3.Performance_ID WHERE T2.Role = "Violin" GROUP BY Date ORDER BY Date DESC
SELECT "Date", COUNT("Date") FROM "member_attendance" "T1" JOIN "member" "T2" ON "T1"."Member_ID" = "T2"."Member_ID" AND "T2"."Role" = "Violin" JOIN "performance" "T3" ON "T1"."Performance_ID" = "T3"."Performance_ID" GROUP BY "Date" ORDER BY "Date" DESC