text: SELECT * FROM (SELECT *
  FROM (
  SELECT DISTINCT qview1."unique2", qview1."evenonepercent", qview1."stringu1", qview1."stringu2", qview2."evenonepercent", qview2."stringu1", qview2."stringu2", qview3."evenonepercent", qview3."stringu1", qview3."stringu2", qview4."evenonepercent", qview4."stringu1", qview4."stringu2"
  FROM
  "public"."t1_1m" qview1,
  "public"."t2_1m" qview2,
  "public"."t3_1m" qview3,
  "public"."t4_1m" qview4
  WHERE
  ((qview1."onepercent" >= 0) AND (qview1."onepercent" < 20)) AND
  qview1."evenonepercent" IS NOT NULL AND
  qview1."stringu2" IS NOT NULL AND
  qview1."stringu1" IS NOT NULL AND
  qview1."unique2" IS NOT NULL AND
  (qview1."unique2" = qview2."unique2") AND
  ((qview2."onepercent" >= 0) AND (qview2."onepercent" < 20)) AND
  qview2."evenonepercent" IS NOT NULL AND
  qview2."stringu2" IS NOT NULL AND
  qview2."stringu1" IS NOT NULL AND
  (qview1."unique2" = qview3."unique2") AND
  ((qview3."onepercent" >= 0) AND (qview3."onepercent" < 20)) AND
  qview3."evenonepercent" IS NOT NULL AND
  qview3."stringu2" IS NOT NULL AND
  qview3."stringu1" IS NOT NULL AND
  (qview1."unique2" = qview4."unique2") AND
  ((qview4."onepercent" >= 0) AND (qview4."onepercent" < 20)) AND
  qview4."evenonepercent" IS NOT NULL AND
  qview4."stringu2" IS NOT NULL AND
  qview4."stringu1" IS NOT NULL
  ) SUB_QVIEW
  
  ) f_1
  