Postgres 15

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create table random_values(id int);

CREATE TABLE


truncate random_values;
insert into random_values (SELECT
    values.value
FROM (
    SELECT
    -- 10000 here is parts which represent 100 by extrapoliated
        FLOOR(random() * 10000) AS random_value
    FROM
    -- here the end is the number of values needed to generate.
        generate_series(1,1000000) i
    ) x,
    ( VALUES
        (1, 0, 7500),     (2, 7501, 9000),  (3, 9001, 9500),
        (4, 9501, 9800),  (5, 9801, 10000)
    ) AS values (value, strt, ending)
WHERE
    x.random_value BETWEEN values.strt AND values.ending
);

TRUNCATE TABLE



INSERT 0 1000000


select *,(count(*)*1.0/1000000)::float from random_values group by 1 order by 1;


id
float8


1
0.750275

2
0.149736

3
0.05017

4
0.029985

5
0.019834



SELECT 5