What is the GDP $IDB in Istanbul?
CREATE TABLE table_name_42 (gdp_in_$id_b VARCHAR, city VARCHAR)
SELECT gdp_in_$id_b FROM table_name_42 WHERE city = "istanbul"
### Context: CREATE TABLE table_name_42 (gdp_in_$id_b VARCHAR, city VARCHAR) ### Question: What is the GDP $IDB in Istanbul? ### Answer: SELECT gdp_in_$id_b FROM table_name_42 WHERE city = "istanbul"