CREATE TABLE "4_6_4_4_6_4_garratt_production_list_all_" (
  "gauge" text,
  "railway" text,
  "class" text,
  "works_no" text,
  "year" text,
  "builder" text
);

Question: Which year has a railway class of 250?
SQL: SELECT "year" FROM "4_6_4_4_6_4_garratt_production_list_all_" WHERE "class"='250';

Question: Which works number has a class of 15th and year of 1940?
SQL: SELECT "works_no" FROM "4_6_4_4_6_4_garratt_production_list_all_" WHERE "class"='15th' AND "year"='1940';

Question: Which builder has a railway of Rhodesia Railways?
SQL: SELECT "builder" FROM "4_6_4_4_6_4_garratt_production_list_all_" WHERE "railway"='rhodesia railways';

Question: Which railway has a class of 250 and year 1936?
SQL: SELECT "railway" FROM "4_6_4_4_6_4_garratt_production_list_all_" WHERE "class"='250' AND "year"='1936';