List the number of active years for attaquant.
CREATE TABLE table_24565004_15 (period VARCHAR, position VARCHAR)
SELECT period FROM table_24565004_15 WHERE position = "Attaquant"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_24565004_15 (period VARCHAR, position VARCHAR) Question: List the number of active years for attaquant. [/INST] SELECT period FROM table_24565004_15 WHERE position = "Attaquant" </s>