SQLite 3.27

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CREATE TABLE numbers (
  `id` INTEGER,
  `number` VARCHAR(8)
);
INSERT INTO numbers
  (`id`, `number`)
VALUES
  ('1', 'singular'),
  ('2', 'dual'),
  ('3', 'plural');
CREATE TABLE cases (
  `id` INTEGER,
  `case` VARCHAR(12)
);
INSERT INTO cases
  (`id`, `case`)
VALUES
  ('1', 'nominative'),
  ('2', 'accusative'),
  ('3', 'instrumental'),
  ('4', 'dative'),
  ('5', 'ablative'),
  ('6', 'genitive'),
  ('7', 'locative'),
  ('8', 'vocative');
CREATE TABLE nouns (
  `id` INTEGER,
  `name` VARCHAR(4)
);
INSERT INTO nouns
  (`id`, `name`)
VALUES
  ('1', 'rAma');
CREATE TABLE forms (
  `id` INTEGER,
  `form` VARCHAR(9),
  `noun` INTEGER
);
INSERT INTO forms
  (`id`, `form`, `noun`)
VALUES
  ('1', 'rAmaH', '1'),
  ('2', 'rAmau', '1'),
  ('3', 'rAmAH', '1'),
  ('4', 'rAmam', '1'),
  ('5', 'rAmAN', '1'),
  ('6', 'rAmENa', '1'),
  ('7', 'rAmAbhyAm', '1'),
  ('8', 'rAmaiH', '1'),
  ('9', 'rAmAya', '1'),
  ('10', 'rAmebhyaH', '1'),
  ('11', 'rAmAt', '1'),
  ('12', 'rAmasya', '1'),
  ('13', 'ramayoH', '1'),
  ('14', 'rAmANAm', '1'),
  ('15', 'rAme', '1'),
  ('16', 'rAmeShu', '1'),
  ('17', 'rAma', '1');
CREATE TABLE nounforms (
  `id` INTEGER,
  `form` INTEGER,
  `case` INTEGER,
  `number` INTEGER,
  `noun` INTEGER
);
INSERT INTO nounforms
  (`id`, `form`, `case`, `number`, `noun`)
VALUES
  ('1', '1', '1', '1', '1'),
  ('2', '2', '1', '2', '1'),
  ('3', '3', '1', '3', '1'),
  ('4', '4', '2', '1', '1'),
  ('5', '2', '2', '2', '1'),
  ('6', '5', '2', '3', '1'),
  ('7', '6', '3', '1', '1'),
  ('8', '7', '3', '2', '1'),
  ('9', '8', '3', '3', '1'),
  ('10', '9', '4', '1', '1'),
  ('11', '7', '4', '2', '1'),
  ('12', '10', '4', '3', '1'),
  ('13', '11', '5', '1', '1'),
  ('14', '7', '5', '2', '1'),
  ('15', '10', '5', '3', '1'),
  ('16', '12', '6', '1', '1'),
  ('17', '13', '6', '2', '1'),
  ('18', '14', '6', '3', '1'),
  ('19', '15', '7', '1', '1'),
  ('20', '13', '7', '2', '1'),
  ('21', '16', '7', '3', '1'),
  ('22', '17', '8', '1', '1'),
  ('23', '2', '8', '2', '1'),
  ('24', '3', '8', '3', '1');
SELECT MAX(CASE WHEN nf.number = 1 THEN f.form END) singular,
       MAX(CASE WHEN nf.number = 2 THEN f.form END) dual,
       MAX(CASE WHEN nf.number = 3 THEN f.form END) plural
FROM forms f 
JOIN nouns n ON n.id = f.noun
JOIN nounforms nf ON f.id = nf.form AND nf.noun = n.id
WHERE n.name = 'rAma'
GROUP BY nf.`case`;


singular
dual
plural


rAmaH
rAmau
rAmAH

rAmam
rAmau
rAmAN

rAmENa
rAmAbhyAm
rAmaiH

rAmAya
rAmAbhyAm
rAmebhyaH

rAmAt
rAmAbhyAm
rAmebhyaH

rAmasya
ramayoH
rAmANAm

rAme
ramayoH
rAmeShu

rAma
rAmau
rAmAH
singular	dual	plural
rAmaH	rAmau	rAmAH
rAmam	rAmau	rAmAN
rAmENa	rAmAbhyAm	rAmaiH
rAmAya	rAmAbhyAm	rAmebhyaH
rAmAt	rAmAbhyAm	rAmebhyaH
rAmasya	ramayoH	rAmANAm
rAme	ramayoH	rAmeShu
rAma	rAmau	rAmAH