-- Density is controllable and bounded across N (v2.0.2 field report: a
-- few-trigram corpus blew up ~50x past 10k rows because the per-tuple
-- positional payload -- positions + bloom -- was stored uncompressed at
-- ~22 B/TID).  That payload path was removed in 3.0.0, so builds are
-- always payload-free.  This test builds the same small-alphabet corpus
-- at 10k and 30k with coalescing ON, and asserts 30k bytes/row stays
-- within 4x of 10k bytes/row (it was 50x).
SET client_min_messages = warning;
SET
CREATE EXTENSION IF NOT EXISTS pg_tre;
CREATE EXTENSION
DROP TABLE IF EXISTS dscale_10k;
DROP TABLE
DROP TABLE IF EXISTS dscale_30k;
DROP TABLE
CREATE TABLE dscale_10k (id serial PRIMARY KEY, body text);
CREATE TABLE
INSERT INTO dscale_10k(body)
SELECT (CASE WHEN g % 2 = 0 THEN 'alpha ' ELSE '' END)
    || (CASE WHEN g % 3 = 0 THEN 'bravo ' ELSE '' END)
    || (CASE WHEN g % 2 = 1 THEN 'charlie ' ELSE '' END)
    || (CASE WHEN g % 5 = 0 THEN 'delta ' ELSE '' END)
    || 'echo foxtrot'
FROM generate_series(1, 10000) g;
INSERT 0 10000
CREATE TABLE dscale_30k (id serial PRIMARY KEY, body text);
CREATE TABLE
INSERT INTO dscale_30k(body)
SELECT (CASE WHEN g % 2 = 0 THEN 'alpha ' ELSE '' END)
    || (CASE WHEN g % 3 = 0 THEN 'bravo ' ELSE '' END)
    || (CASE WHEN g % 2 = 1 THEN 'charlie ' ELSE '' END)
    || (CASE WHEN g % 5 = 0 THEN 'delta ' ELSE '' END)
    || 'echo foxtrot'
FROM generate_series(1, 30000) g;
INSERT 0 30000
SET pg_tre.coalesce_enable = on;
SET
CREATE INDEX dscale_10k_idx ON dscale_10k USING tre (body);
CREATE INDEX
CREATE INDEX dscale_30k_idx ON dscale_30k USING tre (body);
CREATE INDEX
SET pg_tre.coalesce_enable = off;
SET
SELECT CASE WHEN
    (pg_relation_size('dscale_30k_idx') / 30000)
      <= (pg_relation_size('dscale_10k_idx') / 10000) * 4
  THEN 'density_bounded' ELSE 'density_blowup' END AS scaling;
     scaling     
-----------------
 density_bounded
(1 row)

DROP TABLE dscale_10k;
DROP TABLE
DROP TABLE dscale_30k;
DROP TABLE