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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
CREATE TABLE c (
"client_id" INTEGER,
"place_name" VARCHAR(6),
"total purchase" INTEGER,
"detail purchase" INTEGER,
"percent" FLOAT
);
INSERT INTO c
("client_id", "place_name", "total purchase", "detail purchase", "percent")
VALUES
('1', 'place1', 10, 7, 0.7),
('1', 'place2', 10, 3, 0.3),
('2', 'place1', 5, 4, 0.8),
('2', 'place3', 5, 1, 0.2);
4 rows affected