CREATE TABLE table_45197 ("Tie no" TEXT, "Home team" TEXT, "Score" TEXT, "Away team" TEXT, "Date" TEXT)

What was the tie no when Oxford city was the away team?
SELECT "Tie no" FROM table_45197 WHERE "Away team" = 'oxford city'
SELECT "Tie no" FROM "table_45197" WHERE "Away team" = 'oxford city'