mysql tips - JOIN and GROUP BY - complex query example


SELECT td.c1, td.c2, sum(tc.c3) FROM
  (SELECT tc.*, tb.c1, tb.c2 FROM tb
      JOIN (SELECT ta.c1, ta.c2, sum(ta.c3) FROM ta WHERE... GROUP BY...) tc
      ON  tb.c4=ta.c5) td
GROUP BY td.c1, td.c2

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