SQLite 3.27

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CREATE TABLE IF NOT EXISTS tablename (Close_Date TEXT);
INSERT INTO tablename (Close_Date) VALUES 
 ('01/04/2019'),
 ('01/05/2019'),
 ('01/10/2019'),
 ('01/09/2019'),
 ('01/06/2019'),
 ('01/09/2019'),
 ('01/04/2019'),
 ('01/07/2019');
SELECT Close_Date,
       'Q' || COALESCE(NULLIF((SUBSTR(Close_Date, 4, 2) - 1) / 3, 0), 4) AS Quarter
FROM tablename


Close_Date
Quarter


01/04/2019
Q1

01/05/2019
Q1

01/10/2019
Q3

01/09/2019
Q2

01/06/2019
Q1

01/09/2019
Q2

01/04/2019
Q1

01/07/2019
Q2

Close_Date	Quarter
01/04/2019	Q1
01/05/2019	Q1
01/10/2019	Q3
01/09/2019	Q2
01/06/2019	Q1
01/09/2019	Q2
01/04/2019	Q1
01/07/2019	Q2