Oracle 11g Release 2

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CREATE TABLE aeronave (
  id_aeronave NUMBER(10,0) PRIMARY KEY,
  matricula   VARCHAR2(20) NOT NULL
);
CREATE TABLE ocorrencia (
  id_ocorrencia NUMBER(10,0) PRIMARY KEY,
  data_utc      DATE         NOT NULL
);
CREATE TABLE aeronave_ocorrencia (
  id_aeronave   NUMBER(10,0) NOT NULL,
  id_ocorrencia NUMBER(10,0) NOT NULL,
  PRIMARY KEY (id_aeronave, id_ocorrencia),
  FOREIGN KEY (id_aeronave) REFERENCES aeronave (id_aeronave),
  FOREIGN KEY (id_ocorrencia) REFERENCES ocorrencia (id_ocorrencia)
);
INSERT INTO aeronave (id_aeronave, matricula)
VALUES (1, 'Teco-teco');
1 rows affected

INSERT INTO aeronave (id_aeronave, matricula)
VALUES (2, 'Boeing 747');
1 rows affected

INSERT INTO aeronave (id_aeronave, matricula)
VALUES (3, 'Embraer Tucano');
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (1, TO_DATE('2020-08-13', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (2, TO_DATE('2020-07-12', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (3, TO_DATE('2020-06-11', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (4, TO_DATE('2020-05-10', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (5, TO_DATE('2020-04-09', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO ocorrencia (id_ocorrencia, data_utc)
VALUES (6, TO_DATE('2020-03-08', 'YYYY-MM-DD'));
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 6);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 5);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 4);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 3);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 2);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (1, 1);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (3, 1);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (2, 6);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (3, 2);
1 rows affected

INSERT INTO aeronave_ocorrencia (id_aeronave, id_ocorrencia)
VALUES (2, 5);
1 rows affected

SELECT
  a.matricula
FROM
  aeronave a
JOIN 
  aeronave_ocorrencia ao ON a.id_aeronave = ao.id_aeronave
JOIN
  ocorrencia o ON ao.id_ocorrencia = o.id_ocorrencia
WHERE
  o.data_utc > ADD_MONTHS(CAST(SYS_EXTRACT_UTC(SYSTIMESTAMP) AS DATE), -2)
GROUP BY 
  a.matricula;


MATRICULA


Teco-teco

Embraer Tucano