text: -- where2.test
  -- 
  -- execsql {
  --       SELECT w FROM tx
  --        WHERE x IN (SELECT x FROM t1 WHERE +w BETWEEN 200 AND 300)
  --          AND y IN (SELECT y FROM t1 WHERE +w BETWEEN 10 AND 20)
  --          AND z IN (SELECT z FROM t1 WHERE +w BETWEEN 10 AND 20)
  -- }
  SELECT w FROM tx
  WHERE x IN (SELECT x FROM t1 WHERE +w BETWEEN 200 AND 300)
  AND y IN (SELECT y FROM t1 WHERE +w BETWEEN 10 AND 20)
  AND z IN (SELECT z FROM t1 WHERE +w BETWEEN 10 AND 20)