CREATE TABLE table_203_138 (id DECIMAL, "#" DECIMAL, "date" TEXT, "venue" TEXT, "opponent" TEXT, "score" TEXT, "result" TEXT, "competition" TEXT)

how many times was liechtenstein the opponent ?
SELECT COUNT(DISTINCT "date") FROM table_203_138 WHERE "opponent" = 'liechtenstein'
SELECT COUNT(DISTINCT "date") FROM "table_203_138" WHERE "opponent" = 'liechtenstein'