CREATE TABLE table_38860 ("Year" TEXT, "Theme" TEXT, "Host city" TEXT, "Venue" TEXT, "Hosts" TEXT)

What is the host city of the Singapore Indoor Stadium venue and a Valentine's Day theme?
SELECT "Host city" FROM table_38860 WHERE "Venue" = 'singapore indoor stadium' AND "Theme" = 'valentine''s day'
SELECT "Host city" FROM "table_38860" WHERE "Theme" = 'valentine\'s day' AND "Venue" = 'singapore indoor stadium'