WITH (SELECT count(distinct colU) from tabA) AS withA, (SELECT count(distinct colU) from tabA) AS withB SELECT withA / withB AS ratio FROM (SELECT date AS period, colX FROM (SELECT date, if(colA IN (SELECT colB FROM tabC), 0, colA) AS colX FROM tabB) AS tempB GROUP BY period, colX) AS main; -- {serverError 60}
