Tell me the average gross tonnage for april 1919 entered service
CREATE TABLE table_name_57 (gross_tonnage INTEGER, entered_service VARCHAR)
SELECT AVG(gross_tonnage) FROM table_name_57 WHERE entered_service = "april 1919"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_name_57 (gross_tonnage INTEGER, entered_service VARCHAR) Question: Tell me the average gross tonnage for april 1919 entered service [/INST] SELECT AVG(gross_tonnage) FROM table_name_57 WHERE entered_service = "april 1919" </s>