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_12 (bronze INTEGER, rank VARCHAR, total VARCHAR, silver VARCHAR)

### Question ###
I want the average bronze for total of 19 and silver of 8 with rank of 31

### Accurate SQL ###

SELECT AVG(bronze) FROM table_name_12 WHERE total = 19 AND silver = 8 AND rank = "31"