What is the average alcohol content per 12-ounce beer bottle produced by Boston Beer Company?
SELECT AVG(T1.abv) FROM beers AS T1 INNER JOIN breweries AS T2 ON T1.brewery_id = T2.id WHERE T2.name = 'Boston Beer Company' AND T1.ounces = 12
CREATE TABLE breweries
(
    id    INTEGER          not null
        primary key,
    name  TEXT null,
    city  TEXT null,
    state TEXT null
);
CREATE TABLE IF NOT EXISTS "beers"
(
    id         INTEGER not null
        primary key,
    brewery_id INTEGER not null
        constraint beers_ibfk_1
            references breweries,
    abv        REAL,
    ibu        REAL,
    name       TEXT    not null,
    style      TEXT,
    ounces     REAL    not null
);
CREATE INDEX brewery_id
    on beers (brewery_id);
