CREATE TABLE table_203_834 (id DECIMAL, "rank" DECIMAL, "census subdivision" TEXT, "province" TEXT, "type" TEXT, "land area\ ( km2 ,  2011 ) " DECIMAL, "population 2011" DECIMAL, "population 2006" DECIMAL, "population 2001" DECIMAL, "population 1996" DECIMAL, "change in % 2006-2011" DECIMAL, "change in % 1996-2011" DECIMAL)

what was the total population of the five largest cities in the province of ontario in 2006 ?
SELECT SUM("population 2006") FROM table_203_834 WHERE id IN (SELECT id FROM table_203_834 WHERE "province" = 'ontario' ORDER BY "population 2006" DESC LIMIT 5)
SELECT SUM("population 2006") FROM "table_203_834" WHERE "id" IN (SELECT "id" FROM "table_203_834" WHERE "province" = 'ontario' ORDER BY "population 2006" DESC NULLS LAST LIMIT 5)