-- create
CREATE TABLE A (
  ID INTEGER PRIMARY KEY,
  isStatusA BOOLEAN NOT NULL,
  isStatusB BOOLEAN NOT NULL,
  isStatusC BOOLEAN NOT NULL
);

CREATE TABLE B (
  ID INTEGER NOT NULL,
  status text NOT NULL,
  a_id INTEGER NOT NULL
);

-- insert
INSERT INTO A VALUES (0, true, true, false), (1, false, true, false);
INSERT INTO B VALUES (0, 'A', 0), (0, 'C', 0), (1, 'B', 1);

-- fetch 
SELECT A.*, B_agg.status_agg
  FROM A
    INNER JOIN (
      SELECT a_id, ARRAY_AGG(status) status_agg FROM B GROUP BY a_id
    ) B_agg ON A.ID = B_agg.a_id
;