quantile

pig build pkg quantile;		# build rpm/deb

pig repo add pgsql -u   # add both repo and update cache

pig install quantile;		# install via package name, for the active PG version

pig install quantile -v 18;   # install for PG 18
pig install quantile -v 17;   # install for PG 17
pig install quantile -v 16;   # install for PG 16
pig install quantile -v 15;   # install for PG 15
pig install quantile -v 14;   # install for PG 14

CREATE EXTENSION quantile;

CREATE EXTENSION quantile;

-- Compute the median (0.5 quantile)
SELECT quantile(i, 0.5) FROM generate_series(1, 1000) s(i);
-- 500

-- Compute the 95th percentile
SELECT quantile(i, 0.95) FROM generate_series(1, 1000) s(i);

-- Compute all quartiles at once (more efficient than separate calls)
SELECT quantile(i, ARRAY[0.25, 0.5, 0.75])
FROM generate_series(1, 1000) s(i);
-- {250, 500, 750}