Postgres 17

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
CREATE TABLE company_tb (
  "created_at" timestamp,
  "id" INTEGER,
  "name" VARCHAR,
  "nickname" VARCHAR,
  "plan" VARCHAR
);

INSERT INTO company_tb
  ("created_at", "id", "name", "nickname", "plan")
VALUES
  ('2026-03-23 16:11:08', '1', 'AgendaAI Barber Shop', 'agendaai', 'FREE');

CREATE TABLE schedules_tb  (
  "company_id" INTEGER,
  "customer_id" INTEGER,
  "id" INTEGER,
  "schedule" timestamp,
  "service_id" INTEGER,
  "user_id" INTEGER
);

INSERT INTO schedules_tb 
  ("company_id", "customer_id", "id", "schedule", "service_id", "user_id")
VALUES
  ('1', '1', '1', '2026-03-24 10:00:00', '1', '1'),
  ('1', '2', '2', '2026-03-24 11:00:00', '3', '1'),
  ('1', '3', '3', '2026-03-24 12:00:00', '1', '1'),
  ('1', '4', '4', '2026-03-24 15:00:00', '1', '1'),
  ('1', '5', '5', '2026-03-25 08:00:00', '2', '1'),
  ('1', '6', '6', '2026-03-25 10:00:00', '1', '1'),
  ('1', '7', '7', '2026-03-26 10:00:00', '1', '1');

CREATE TABLE users_tb (
  "company_id" INTEGER,
  "id" INTEGER,
  "created_at" timestamp,
  "email" VARCHAR,
  "name" VARCHAR,
  "role" VARCHAR
);

INSERT INTO users_tb
  ("company_id", "id", "created_at", "email", "name", "role")
VALUES
  ('1', '1', '2026-03-24 10:00:00', 'email@mail', 'John Doe', 'ADM'),
  ('1', '2', '2026-03-24 11:00:00', 'email@mail', 'Ian F', 'USER');

CREATE TABLE services_tb (
  "duration" INTEGER,
  "price" INTEGER,
  "id" INTEGER,
  "company_id" INTEGER,
  "desc" VARCHAR,
  "name" VARCHAR
);

INSERT INTO services_tb
  ("duration", "price", "id", "company_id", "desc", "name")
VALUES
  ('60', '40', '1', '1', 'Classic men''s haircut', 'Haircut'),
  ('20', '20', '2', '1', 'Beard trimming', 'Beard trim');

CREATE TABLE



INSERT 0 1



CREATE TABLE



INSERT 0 7



CREATE TABLE



INSERT 0 2



CREATE TABLE



INSERT 0 2


CREATE or replace FUNCTION get_appointment
  (customerName varchar, companyNickname varchar)
RETURNS TABLE (name varchar, duration int, scheduled timestamp)
as $$
    SELECT
      u.name,
      sv.duration,
      sc.schedule
    from company_tb c
    join schedules_tb sc on c.id = sc.company_id
    join users_tb u on c.id = u.company_id and sc.user_id = u.id
    join services_tb sv on c.id = sv.company_id and sc.service_id = sv.id
    where (u.name = customerName or customerName is null or customerName = '')
      and c.nickname = companyNickname
      and sc.schedule > CURRENT_TIMESTAMP;
    $$LANGUAGE sql;

CREATE FUNCTION


SELECT * from get_appointment('', 'agendaai');


name
duration
scheduled


John Doe
20
2026-03-25 08:00:00

John Doe
60
2026-03-25 10:00:00

John Doe
60
2026-03-26 10:00:00



SELECT 3
name	duration	scheduled
John Doe	20	2026-03-25 08:00:00
John Doe	60	2026-03-25 10:00:00
John Doe	60	2026-03-26 10:00:00