Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_19 (date INTEGER, works_number VARCHAR, builder VARCHAR, number VARCHAR)
### Question:
Which Date has a Builder of alco schenectady, and a Number larger than 835, and Works number of 56566?
### Answer:
SELECT AVG(date) FROM table_name_19 WHERE builder = "alco schenectady" AND number > 835 AND works_number = 56566