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_2801442_1 ( area__km²_ INTEGER, code VARCHAR )

### Question ###
How big (in km2) is the district with a code BW?

### Accurate SQL ###

SELECT MIN(area__km²_) FROM table_2801442_1 WHERE code = "BW"