• Clone current repository git clone ...
• Move to almanac folder cd almanac
• Copy and modify .env file cp .env.example .env
• Create database: docker-compose run api rails db:create db:migrate
• Start cointainers: docker-compose up -d -- postgresql Postgresql database -- pgadmin Pgadmin4 for pgsql interface -- swagger Swagger web server for documentation -- api Thin web server for api requests
• Seed database. One of two ways: -- docker-compose run --rm -e "DB_SEED=true" api rails db:seed - Use database for seed -- docker-compose run --rm -e "CURL_SEED=true" api rails db:seed - Use curl for seed

Swagger docs

create temp table users(id bigserial, group_id bigint);
insert into users(group_id) values (1), (1), (1), (2), (1), (3);

SELECT MIN(id) as min_id, MIN(group_id) as group_id, COUNT(*)
FROM (
  SELECT *, SUM(group_row_number::int) OVER (ORDER BY id) as group_sequence_num
  FROM (
    SELECT *, CASE WHEN (LAG(group_id) OVER (ORDER BY id)) = group_id THEN 0 ELSE 1 END as group_row_number FROM users
  ) AS first_table
) AS second_table
GROUP BY group_sequence_num
ORDER BY min_id