risk_score result for each of month - sql

Question

I want to generate highest risk_score result for each of month (Jan, Feb & Mar)
Displaying the following columns: Firm_id_1, risk_score_Jan, risk_score_Feb, risk_score_Mar
CREATE table firm_risk (
firm_id_1 INT,
assessment_date DATE,
risk_score FLOAT
);
INSERT INTO firm_risk (firm_id_1, assessment_date, risk_score)
VALUES (123, '1/01/2018', 0.43),
(123, '1/28/2018', 0.80),
(123, '2/11/2018', 0.28),
(123, '2/23/2018', 0.91),
(123, '3/11/2018', 0.08),
(123, '3/31/2018', 0.60),
(456, '1/4/2018', 0.87),
(456, '1/6/2018', 0.02),
(456, '1/20/2018', 0.39),
(456, '2/3/2018', 0.10),
(456, '3/1/2018', 0.12),
(789, '1/1/2018', 0.20),
(789, '3/1/2018', 0.17);
SELECT * FROM firm_risk;
SELECT firm_id_1, date_part('month', assessment_date) AS AD
FROM firm_risk
WHERE assessment_date = (SELECT MAX (assessment_date) FROM firm_risk)
GROUP BY firm_id_1, risk_score, assessment_date;
CREATE table latest_risk_score (
firm_id_2 integer,
latest_risk_score_Jan float,
latest_risk_score_Feb float,
latest_risk_score_Mar float
);
SELECT * FROM latest_risk_score;
INSERT INTO latest_risk_score (firm_id_2)
VALUES (123),
(456),
(789);
SELECT firm_risk.firm_id_1, date_part('month', assessment_date), firm_risk.risk_score
FROM firm_risk
INNER JOIN latest_risk_score
ON firm_risk.firm_id_1 = latest_risk_score.firm_id_2
GROUP BY firm_risk.firm_id_1, firm_risk.risk_score, assessment_date;
SELECT firm_risk.firm_id_1, date_part('month', assessment_date), firm_risk.risk_score
FROM firm_risk
WHERE assessment_date = (SELECT MAX (assessment_date) FROM firm_risk)
AND assessment_date LIKE '_%-01-2018%';
SELECT firm_risk.firm_id_1, date_part('month', assessment_date)
FROM firm_risk
WHERE assessment_date >= date_part('month', assessment_date - '3 months')
GROUP BY firm_risk.firm_id_1, ('month', assessment_date);
UPDATE latest_risk_score SET latest_risk_score_Jan = (SELECT Risk_Score FROM firm_risk.firm_id_1 WHERE Assessment_Date = (SELECT MAX(Assessment_Date)
FROM firm_risk.firm_id_1 WHERE firm_id_1 = 123 AND Assessment_Date LIKE "2018-01-%" ORDER BY Assessment_Date))
WHERE firm_id_1 = 123;
update latest_risk_score
set latest_risk_score_Feb = (select Risk_Score from firm_risk.firm_id_1 where Assessment_Date = (select max(Assessment_Date)
from firm_risk.firm_id_1 where firm_id_1 = 123 and Assessment_Date like "2018-02-%" order by Assessment_Date))
where firm_id_1 = 123;
update latest_risk_score
set latest_risk_score_Mar = (select Risk_Score from firm_risk.firm_id_1 where Assessment_Date = (select max(Assessment_Date)
from firm_risk.firm_id_1 where firm_id_1 = 123 and Assessment_Date like "2018-03-%" order by Assessment_Date))
where firm_id_1 = 123;
select * from latest_risk_score;

Answer 1

Assuming postgres is relevant (due to existence of "date_part" in question)
CREATE table firm_risk (
firm_id_1 INT,
assessment_date DATE,
risk_score FLOAT
);
INSERT INTO firm_risk (firm_id_1, assessment_date, risk_score)
VALUES (123, '2018-01-01', 0.43),
(123, '2018-01-28', 0.80),
(123, '2018-02-11', 0.28),
(123, '2018-02-23', 0.91),
(123, '2018-03-11', 0.08),
(123, '2018-03-31', 0.60),
(456, '2018-01-04', 0.87),
(456, '2018-01-06', 0.02),
(456, '2018-01-20', 0.39),
(456, '2018-02-03', 0.10),
(456, '2018-03-01', 0.12),
(789, '2018-01-01', 0.20),
(789, '2018-03-01', 0.17);
SELECT
firm_risk.firm_id_1
, max(case when date_part('month',assessment_date) = 1 then firm_risk.risk_score end) jan_risk
, max(case when date_part('month',assessment_date) = 2 then firm_risk.risk_score end) feb_risk
, max(case when date_part('month',assessment_date) = 3 then firm_risk.risk_score end) mar_risk
FROM firm_risk
WHERE date_part('month',assessment_date) in (1,2,3)
GROUP BY
firm_risk.firm_id_1
firm_id_1 | jan_risk | feb_risk | mar_risk
--------: | :------- | :------- | :-------
789 | 0.2 | null | 0.17
456 | 0.87 | 0.1 | 0.12
123 | 0.8 | 0.91 | 0.6
db<>fiddle here