Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_19 ( opp_team VARCHAR, big_ten_team VARCHAR )

### Question ###
Who was Purdue's opponent?

### Accurate SQL ###

SELECT opp_team FROM table_name_19 WHERE big_ten_team = "purdue"