Name the barrel length for rear sight a2 for factory compensator
CREATE TABLE table_12834315_4 (barrel_length VARCHAR, rear_sight VARCHAR, muzzle_device VARCHAR)
SELECT barrel_length FROM table_12834315_4 WHERE rear_sight = "A2" AND muzzle_device = "Factory compensator"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_12834315_4 (barrel_length VARCHAR, rear_sight VARCHAR, muzzle_device VARCHAR) Question: Name the barrel length for rear sight a2 for factory compensator [/INST] SELECT barrel_length FROM table_12834315_4 WHERE rear_sight = "A2" AND muzzle_device = "Factory compensator" </s>