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_12108_1 (gdp___bn__ VARCHAR)

### Question ###
what is the gdp ( bn ) where capital is capital?

### Accurate SQL ###

SELECT gdp___bn__ FROM table_12108_1 WHERE "capital" = "capital"