Danilo Alessandro Vinciprova

Danilo Alessandro Vinciprova

AI-Assisted Web Developer · React · Next.js · Claude Code

Aprendí a pensar en construir como en piezas que tienen que encajar entre sí.

Habilidad 02 / 03

SQL y PostgreSQL

Dos esquemas de bases de datos dibujados a partir de sus archivos SQL, y las consultas de un script de Bash.

  • SQL, PostgreSQL y Bash(verificado)
(verificado) marca una habilidad verificada

Resumen

Dos proyectos de bases de datos de freeCodeCamp, de mis repositorios públicos: un esquema PostgreSQL de galaxias, estrellas, planetas y lunas, y una agenda de citas para una peluquería escrita en Bash sobre psql. Los diagramas se dibujan a partir de los propios archivos SQL.

En esta página

  1. 02 Esquema: dos diagramas de entidades, dibujados al compilar a partir de los archivos SQL
  2. 03 Consultas: las líneas de consulta del script de la peluquería
  3. 04 Pruebas: los 2 certificados Relational Database y los 2 repositorios

SQL, PostgreSQL y Bash (verificado)

Ver la prueba

  1. Afirmación

    SQL, PostgreSQL y Bash

    ✓ Verificado

  2. Pruebas

  3. Resultado

    Dos certificaciones Relational Database de freeCodeCamp (una con 5 proyectos) y dos proyectos públicos de bases de datos en GitHub.

Quién escribió este código

“Escribí el código de los ejercicios de freeCodeCamp que se muestra en las páginas de habilidades.”

Ver la prueba

  1. Afirmación

    Escribí el código de los ejercicios de freeCodeCamp que se muestra en las páginas de habilidades.

    Declarado por Danilo

  2. Pruebas

  3. Resultado

    El código está copiado literalmente de repositorios públicos, donde los commits los hizo la cuenta de GitHub de Danilo (zurukzuruk1). Que lo escribiera él mismo es una declaración suya del 2 oct 2026.

Esquema

Los dos diagramas se generan al compilar el sitio, leyendo las sentencias CREATE TABLE y las restricciones de claves de los archivos SQL literales: columnas y tipos, claves primarias, columnas únicas y claves foráneas. Nada se dibuja a mano.

Base de datos de cuerpos celestes: universe.sql

Nivel de prueba: Prueba existente · dibujado a partir del archivo

5 tablas · 4 claves foráneas · 27 columnas

galaxy_typePKgalaxy_type_idintegerUQnamecharacter varying(255)descriptiontextgalaxyPKgalaxy_idintegerUQnamecharacter varying(255)FKgalaxy_type_idintegerdistance_from_earthnumerichas_dark_matterbooleandiameter_light_yearsintegerplanetPKplanet_idintegerUQnamecharacter varying(255)FKstar_idintegerhas_ringsbooleanorbital_period_daysnumericmoons_countintegerstarPKstar_idintegerUQnamecharacter varying(255)FKgalaxy_idintegermass_solar_massesnumericis_variablebooleanage_million_yearsintegermoonPKmoon_idintegerUQnamecharacter varying(255)FKplanet_idintegerhas_atmospherebooleandiameter_kmnumericdiscovery_yearintegergalaxy_typePKgalaxy_type_idintegerUQnamecharacter varying(255)descriptiontextgalaxyPKgalaxy_idintegerUQnamecharacter varying(255)FKgalaxy_type_idintegerdistance_from_earthnumerichas_dark_matterbooleandiameter_light_yearsintegerstarPKstar_idintegerUQnamecharacter varying(255)FKgalaxy_idintegermass_solar_massesnumericis_variablebooleanage_million_yearsintegerplanetPKplanet_idintegerUQnamecharacter varying(255)FKstar_idintegerhas_ringsbooleanorbital_period_daysnumericmoons_countintegermoonPKmoon_idintegerUQnamecharacter varying(255)FKplanet_idintegerhas_atmospherebooleandiameter_kmnumericdiscovery_yearinteger
Diagrama de entidades de universe.sql: 5 tablas y 4 claves foráneas, leídas del archivo al generar este sitio. Cada línea une una columna de clave foránea (○) con la columna a la que hace referencia (●). PK clave primaria, FK clave foránea, UQ única.
Tablas, columnas y claves como texto

galaxy

ColumnaTipoNo nuloClaves
galaxy_idintegersíclave primaria
namecharacter varying(255)síúnica
galaxy_type_idintegernoclave foránea
distance_from_earthnumericsí–
has_dark_matterbooleanno–
diameter_light_yearsintegerno–

galaxy_type

ColumnaTipoNo nuloClaves
galaxy_type_idintegersíclave primaria
namecharacter varying(255)síúnica
descriptiontextsí–

moon

ColumnaTipoNo nuloClaves
moon_idintegersíclave primaria
namecharacter varying(255)síúnica
planet_idintegersíclave foránea
has_atmospherebooleanno–
diameter_kmnumericno–
discovery_yearintegerno–

planet

ColumnaTipoNo nuloClaves
planet_idintegersíclave primaria
namecharacter varying(255)síúnica
star_idintegersíclave foránea
has_ringsbooleanno–
orbital_period_daysnumericno–
moons_countintegerno–

star

ColumnaTipoNo nuloClaves
star_idintegersíclave primaria
namecharacter varying(255)síúnica
galaxy_idintegersíclave foránea
mass_solar_massesnumericno–
is_variablebooleanno–
age_million_yearsintegerno–

Claves foráneas

ColumnaReferencia
galaxy.galaxy_type_idgalaxy_type.galaxy_type_id
moon.planet_idplanet.planet_id
planet.star_idstar.star_id
star.galaxy_idgalaxy.galaxy_id

universe.sql líneas 1–464

Raw: texto de universe.sql, líneas 1–464Repo: repositorio celestial-bodies-database en GitHub
Mostrar el archivo completo (464 líneas)
--
-- PostgreSQL database dump
--

-- Dumped from database version 12.22 (Ubuntu 12.22-0ubuntu0.20.04.4)
-- Dumped by pg_dump version 12.22 (Ubuntu 12.22-0ubuntu0.20.04.4)

SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;

SET default_tablespace = '';

SET default_table_access_method = heap;

--
-- Name: galaxy; Type: TABLE; Schema: public; Owner: -
--

CREATE TABLE public.galaxy (
    galaxy_id integer NOT NULL,
    name character varying(255) NOT NULL,
    galaxy_type_id integer,
    distance_from_earth numeric NOT NULL,
    has_dark_matter boolean,
    diameter_light_years integer
);


--
-- Name: galaxy_galaxy_id_seq; Type: SEQUENCE; Schema: public; Owner: -
--

CREATE SEQUENCE public.galaxy_galaxy_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


--
-- Name: galaxy_galaxy_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
--

ALTER SEQUENCE public.galaxy_galaxy_id_seq OWNED BY public.galaxy.galaxy_id;


--
-- Name: galaxy_type; Type: TABLE; Schema: public; Owner: -
--

CREATE TABLE public.galaxy_type (
    galaxy_type_id integer NOT NULL,
    name character varying(255) NOT NULL,
    description text NOT NULL
);


--
-- Name: galaxy_type_galaxy_type_id_seq; Type: SEQUENCE; Schema: public; Owner: -
--

CREATE SEQUENCE public.galaxy_type_galaxy_type_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


--
-- Name: galaxy_type_galaxy_type_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
--

ALTER SEQUENCE public.galaxy_type_galaxy_type_id_seq OWNED BY public.galaxy_type.galaxy_type_id;


--
-- Name: moon; Type: TABLE; Schema: public; Owner: -
--

CREATE TABLE public.moon (
    moon_id integer NOT NULL,
    name character varying(255) NOT NULL,
    planet_id integer NOT NULL,
    has_atmosphere boolean,
    diameter_km numeric,
    discovery_year integer
);


--
-- Name: moon_moon_id_seq; Type: SEQUENCE; Schema: public; Owner: -
--

CREATE SEQUENCE public.moon_moon_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


--
-- Name: moon_moon_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
--

ALTER SEQUENCE public.moon_moon_id_seq OWNED BY public.moon.moon_id;


--
-- Name: planet; Type: TABLE; Schema: public; Owner: -
--

CREATE TABLE public.planet (
    planet_id integer NOT NULL,
    name character varying(255) NOT NULL,
    star_id integer NOT NULL,
    has_rings boolean,
    orbital_period_days numeric,
    moons_count integer
);


--
-- Name: planet_planet_id_seq; Type: SEQUENCE; Schema: public; Owner: -
--

CREATE SEQUENCE public.planet_planet_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


--
-- Name: planet_planet_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
--

ALTER SEQUENCE public.planet_planet_id_seq OWNED BY public.planet.planet_id;


--
-- Name: star; Type: TABLE; Schema: public; Owner: -
--

CREATE TABLE public.star (
    star_id integer NOT NULL,
    name character varying(255) NOT NULL,
    galaxy_id integer NOT NULL,
    mass_solar_masses numeric,
    is_variable boolean,
    age_million_years integer
);


--
-- Name: star_star_id_seq; Type: SEQUENCE; Schema: public; Owner: -
--

CREATE SEQUENCE public.star_star_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


--
-- Name: star_star_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
--

ALTER SEQUENCE public.star_star_id_seq OWNED BY public.star.star_id;


--
-- Name: galaxy galaxy_id; Type: DEFAULT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy ALTER COLUMN galaxy_id SET DEFAULT nextval('public.galaxy_galaxy_id_seq'::regclass);


--
-- Name: galaxy_type galaxy_type_id; Type: DEFAULT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy_type ALTER COLUMN galaxy_type_id SET DEFAULT nextval('public.galaxy_type_galaxy_type_id_seq'::regclass);


--
-- Name: moon moon_id; Type: DEFAULT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.moon ALTER COLUMN moon_id SET DEFAULT nextval('public.moon_moon_id_seq'::regclass);


--
-- Name: planet planet_id; Type: DEFAULT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.planet ALTER COLUMN planet_id SET DEFAULT nextval('public.planet_planet_id_seq'::regclass);


--
-- Name: star star_id; Type: DEFAULT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.star ALTER COLUMN star_id SET DEFAULT nextval('public.star_star_id_seq'::regclass);


--
-- Data for Name: galaxy; Type: TABLE DATA; Schema: public; Owner: -
--

COPY public.galaxy (galaxy_id, name, galaxy_type_id, distance_from_earth, has_dark_matter, diameter_light_years) FROM stdin;
1	Milky Way	1	0	t	105700
2	Andromeda	1	2537000	t	220000
3	Triangulum	1	2723000	t	60000
4	Whirlpool	1	23160000	t	76000
5	Cartwheel	3	500000000	t	150000
6	Sombrero	4	29350000	t	50000
\.


--
-- Data for Name: galaxy_type; Type: TABLE DATA; Schema: public; Owner: -
--

COPY public.galaxy_type (galaxy_type_id, name, description) FROM stdin;
1	Spiral	A galaxy with a flat, rotating disk containing stars, gas and dust, and a central concentration of stars
2	Elliptical	A galaxy with an ellipsoidal shape and a smooth, nearly featureless brightness profile
3	Irregular	A galaxy that does not have a distinct regular shape
4	Lenticular	A galaxy intermediate between elliptical and spiral galaxies
\.


--
-- Data for Name: moon; Type: TABLE DATA; Schema: public; Owner: -
--

COPY public.moon (moon_id, name, planet_id, has_atmosphere, diameter_km, discovery_year) FROM stdin;
1	The Moon	3	f	3474.8	\N
2	Phobos	4	f	22.2	1877
3	Deimos	4	f	12.4	1877
4	Io	5	f	3643.2	1610
5	Europa	5	f	3121.6	1610
6	Ganymede	5	t	5268.2	1610
7	Callisto	5	f	4820.6	1610
8	Amalthea	5	f	167	1892
9	Titan	6	t	5149.5	1655
10	Rhea	6	f	1527	1672
11	Iapetus	6	f	1469	1671
12	Dione	6	f	1123	1684
13	Tethys	6	f	1062	1684
14	Enceladus	6	f	504	1789
15	Titania	7	f	1578	1787
16	Oberon	7	f	1523	1787
17	Umbriel	7	f	1169	1851
18	Ariel	7	f	1158	1851
19	Miranda	7	f	471	1948
20	Triton	8	t	2706.8	1846
21	Nereid	8	f	340	1949
\.


--
-- Data for Name: planet; Type: TABLE DATA; Schema: public; Owner: -
--

COPY public.planet (planet_id, name, star_id, has_rings, orbital_period_days, moons_count) FROM stdin;
1	Mercury	1	f	88	0
2	Venus	1	f	224.7	0
3	Earth	1	f	365.25	1
4	Mars	1	f	687	2
5	Jupiter	1	t	4331	4
6	Saturn	1	t	10747	5
7	Uranus	1	t	30589	3
8	Neptune	1	t	59800	2
9	Proxima b	6	f	11.2	0
10	Sirius Ab	2	f	300	0
11	Rigel b	4	f	500	0
12	Centauri Bb	5	f	3.2	0
\.


--
-- Data for Name: star; Type: TABLE DATA; Schema: public; Owner: -
--

COPY public.star (star_id, name, galaxy_id, mass_solar_masses, is_variable, age_million_years) FROM stdin;
1	Sun	1	1.0	f	4600
2	Sirius	1	2.02	f	242
3	Betelgeuse	1	16.5	t	10
4	Rigel	1	21	t	8
5	Alpha Centauri A	1	1.1	f	4850
6	Proxima Centauri	1	0.12	t	4850
\.


--
-- Name: galaxy_galaxy_id_seq; Type: SEQUENCE SET; Schema: public; Owner: -
--

SELECT pg_catalog.setval('public.galaxy_galaxy_id_seq', 6, true);


--
-- Name: galaxy_type_galaxy_type_id_seq; Type: SEQUENCE SET; Schema: public; Owner: -
--

SELECT pg_catalog.setval('public.galaxy_type_galaxy_type_id_seq', 4, true);


--
-- Name: moon_moon_id_seq; Type: SEQUENCE SET; Schema: public; Owner: -
--

SELECT pg_catalog.setval('public.moon_moon_id_seq', 21, true);


--
-- Name: planet_planet_id_seq; Type: SEQUENCE SET; Schema: public; Owner: -
--

SELECT pg_catalog.setval('public.planet_planet_id_seq', 12, true);


--
-- Name: star_star_id_seq; Type: SEQUENCE SET; Schema: public; Owner: -
--

SELECT pg_catalog.setval('public.star_star_id_seq', 6, true);


--
-- Name: galaxy galaxy_name_key; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy
    ADD CONSTRAINT galaxy_name_key UNIQUE (name);


--
-- Name: galaxy galaxy_pkey; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy
    ADD CONSTRAINT galaxy_pkey PRIMARY KEY (galaxy_id);


--
-- Name: galaxy_type galaxy_type_name_key; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy_type
    ADD CONSTRAINT galaxy_type_name_key UNIQUE (name);


--
-- Name: galaxy_type galaxy_type_pkey; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy_type
    ADD CONSTRAINT galaxy_type_pkey PRIMARY KEY (galaxy_type_id);


--
-- Name: moon moon_name_key; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.moon
    ADD CONSTRAINT moon_name_key UNIQUE (name);


--
-- Name: moon moon_pkey; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.moon
    ADD CONSTRAINT moon_pkey PRIMARY KEY (moon_id);


--
-- Name: planet planet_name_key; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.planet
    ADD CONSTRAINT planet_name_key UNIQUE (name);


--
-- Name: planet planet_pkey; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.planet
    ADD CONSTRAINT planet_pkey PRIMARY KEY (planet_id);


--
-- Name: star star_name_key; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.star
    ADD CONSTRAINT star_name_key UNIQUE (name);


--
-- Name: star star_pkey; Type: CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.star
    ADD CONSTRAINT star_pkey PRIMARY KEY (star_id);


--
-- Name: galaxy galaxy_galaxy_type_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.galaxy
    ADD CONSTRAINT galaxy_galaxy_type_id_fkey FOREIGN KEY (galaxy_type_id) REFERENCES public.galaxy_type(galaxy_type_id);


--
-- Name: moon moon_planet_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.moon
    ADD CONSTRAINT moon_planet_id_fkey FOREIGN KEY (planet_id) REFERENCES public.planet(planet_id);


--
-- Name: planet planet_star_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.planet
    ADD CONSTRAINT planet_star_id_fkey FOREIGN KEY (star_id) REFERENCES public.star(star_id);


--
-- Name: star star_galaxy_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: -
--

ALTER TABLE ONLY public.star
    ADD CONSTRAINT star_galaxy_id_fkey FOREIGN KEY (galaxy_id) REFERENCES public.galaxy(galaxy_id);


--
-- PostgreSQL database dump complete
--

Nivel de prueba: Prueba existente

Base de datos de cuerpos celestes: el archivo SQL completo · copiado el 2 de octubre de 2026 · sha256 5404507373b9…

Agenda de citas para una peluquería: salon.sql

Nivel de prueba: Prueba existente · dibujado a partir del archivo

3 tablas · 2 claves foráneas · 9 columnas

customersPKcustomer_idintegerUQphonecharacter varying(20)namecharacter varying(50)appointmentsPKappointment_idintegerFKcustomer_idintegerFKservice_idintegertimecharacter varying(20)servicesPKservice_idintegernamecharacter varying(50)customersPKcustomer_idintegerUQphonecharacter varying(20)namecharacter varying(50)appointmentsPKappointment_idintegerFKcustomer_idintegerFKservice_idintegertimecharacter varying(20)servicesPKservice_idintegernamecharacter varying(50)
Diagrama de entidades de salon.sql: 3 tablas y 2 claves foráneas, leídas del archivo al generar este sitio. Cada línea une una columna de clave foránea (○) con la columna a la que hace referencia (●). PK clave primaria, FK clave foránea, UQ única.
Tablas, columnas y claves como texto

appointments

ColumnaTipoNo nuloClaves
appointment_idintegersíclave primaria
customer_idintegersíclave foránea
service_idintegersíclave foránea
timecharacter varying(20)sí–

customers

ColumnaTipoNo nuloClaves
customer_idintegersíclave primaria
phonecharacter varying(20)síúnica
namecharacter varying(50)sí–

services

ColumnaTipoNo nuloClaves
service_idintegersíclave primaria
namecharacter varying(50)sí–

Claves foráneas

ColumnaReferencia
appointments.customer_idcustomers.customer_id
appointments.service_idservices.service_id

salon.sql líneas 1–267

Raw: texto de salon.sql, líneas 1–267Repo: repositorio salon-appointment-scheduler en GitHub
Mostrar el archivo completo (267 líneas)
--
-- PostgreSQL database dump
--

-- Dumped from database version 12.22 (Ubuntu 12.22-0ubuntu0.20.04.4)
-- Dumped by pg_dump version 12.22 (Ubuntu 12.22-0ubuntu0.20.04.4)

SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;

DROP DATABASE salon;
--
-- Name: salon; Type: DATABASE; Schema: -; Owner: freecodecamp
--

CREATE DATABASE salon WITH TEMPLATE = template0 ENCODING = 'UTF8' LC_COLLATE = 'C.UTF-8' LC_CTYPE = 'C.UTF-8';


ALTER DATABASE salon OWNER TO freecodecamp;

\connect salon

SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;

SET default_tablespace = '';

SET default_table_access_method = heap;

--
-- Name: appointments; Type: TABLE; Schema: public; Owner: freecodecamp
--

CREATE TABLE public.appointments (
    appointment_id integer NOT NULL,
    customer_id integer NOT NULL,
    service_id integer NOT NULL,
    "time" character varying(20) NOT NULL
);


ALTER TABLE public.appointments OWNER TO freecodecamp;

--
-- Name: appointments_appointment_id_seq; Type: SEQUENCE; Schema: public; Owner: freecodecamp
--

CREATE SEQUENCE public.appointments_appointment_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


ALTER TABLE public.appointments_appointment_id_seq OWNER TO freecodecamp;

--
-- Name: appointments_appointment_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: freecodecamp
--

ALTER SEQUENCE public.appointments_appointment_id_seq OWNED BY public.appointments.appointment_id;


--
-- Name: customers; Type: TABLE; Schema: public; Owner: freecodecamp
--

CREATE TABLE public.customers (
    customer_id integer NOT NULL,
    phone character varying(20) NOT NULL,
    name character varying(50) NOT NULL
);


ALTER TABLE public.customers OWNER TO freecodecamp;

--
-- Name: customers_customer_id_seq; Type: SEQUENCE; Schema: public; Owner: freecodecamp
--

CREATE SEQUENCE public.customers_customer_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


ALTER TABLE public.customers_customer_id_seq OWNER TO freecodecamp;

--
-- Name: customers_customer_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: freecodecamp
--

ALTER SEQUENCE public.customers_customer_id_seq OWNED BY public.customers.customer_id;


--
-- Name: services; Type: TABLE; Schema: public; Owner: freecodecamp
--

CREATE TABLE public.services (
    service_id integer NOT NULL,
    name character varying(50) NOT NULL
);


ALTER TABLE public.services OWNER TO freecodecamp;

--
-- Name: services_service_id_seq; Type: SEQUENCE; Schema: public; Owner: freecodecamp
--

CREATE SEQUENCE public.services_service_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;


ALTER TABLE public.services_service_id_seq OWNER TO freecodecamp;

--
-- Name: services_service_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: freecodecamp
--

ALTER SEQUENCE public.services_service_id_seq OWNED BY public.services.service_id;


--
-- Name: appointments appointment_id; Type: DEFAULT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.appointments ALTER COLUMN appointment_id SET DEFAULT nextval('public.appointments_appointment_id_seq'::regclass);


--
-- Name: customers customer_id; Type: DEFAULT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.customers ALTER COLUMN customer_id SET DEFAULT nextval('public.customers_customer_id_seq'::regclass);


--
-- Name: services service_id; Type: DEFAULT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.services ALTER COLUMN service_id SET DEFAULT nextval('public.services_service_id_seq'::regclass);


--
-- Data for Name: appointments; Type: TABLE DATA; Schema: public; Owner: freecodecamp
--



--
-- Data for Name: customers; Type: TABLE DATA; Schema: public; Owner: freecodecamp
--



--
-- Data for Name: services; Type: TABLE DATA; Schema: public; Owner: freecodecamp
--

INSERT INTO public.services VALUES (1, 'cut');
INSERT INTO public.services VALUES (2, 'color');
INSERT INTO public.services VALUES (3, 'perm');
INSERT INTO public.services VALUES (4, 'style');
INSERT INTO public.services VALUES (5, 'trim');


--
-- Name: appointments_appointment_id_seq; Type: SEQUENCE SET; Schema: public; Owner: freecodecamp
--

SELECT pg_catalog.setval('public.appointments_appointment_id_seq', 6, true);


--
-- Name: customers_customer_id_seq; Type: SEQUENCE SET; Schema: public; Owner: freecodecamp
--

SELECT pg_catalog.setval('public.customers_customer_id_seq', 5, true);


--
-- Name: services_service_id_seq; Type: SEQUENCE SET; Schema: public; Owner: freecodecamp
--

SELECT pg_catalog.setval('public.services_service_id_seq', 5, true);


--
-- Name: appointments appointments_pkey; Type: CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.appointments
    ADD CONSTRAINT appointments_pkey PRIMARY KEY (appointment_id);


--
-- Name: customers customers_phone_key; Type: CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.customers
    ADD CONSTRAINT customers_phone_key UNIQUE (phone);


--
-- Name: customers customers_pkey; Type: CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.customers
    ADD CONSTRAINT customers_pkey PRIMARY KEY (customer_id);


--
-- Name: services services_pkey; Type: CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.services
    ADD CONSTRAINT services_pkey PRIMARY KEY (service_id);


--
-- Name: appointments appointments_customer_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.appointments
    ADD CONSTRAINT appointments_customer_id_fkey FOREIGN KEY (customer_id) REFERENCES public.customers(customer_id);


--
-- Name: appointments appointments_service_id_fkey; Type: FK CONSTRAINT; Schema: public; Owner: freecodecamp
--

ALTER TABLE ONLY public.appointments
    ADD CONSTRAINT appointments_service_id_fkey FOREIGN KEY (service_id) REFERENCES public.services(service_id);


--
-- PostgreSQL database dump complete
--

Nivel de prueba: Prueba existente

Agenda de citas para una peluquería: el archivo SQL completo · copiado el 2 de octubre de 2026 · sha256 9bca9e9176eb…

Consultas

El script de la peluquería envía su SQL a PostgreSQL mediante psql: 6 sentencias (SELECT, INSERT) en estas líneas, desde listar los servicios hasta reservar la cita.

Las sentencias, en orden

Nivel de prueba: Prueba existente

  1. línea 14SELECT service_id, name FROM services ORDER BY service_id
  2. línea 31SELECT name FROM services WHERE service_id = $SERVICE_ID_SELECTED
  3. línea 42SELECT name FROM customers WHERE phone = '$CUSTOMER_PHONE'
  4. línea 47INSERT INTO customers(phone, name) VALUES('$CUSTOMER_PHONE', '$CUSTOMER_NAME')
  5. línea 51SELECT customer_id FROM customers WHERE phone = '$CUSTOMER_PHONE'
  6. línea 57INSERT INTO appointments(customer_id, service_id, time) VALUES($CUSTOMER_ID, $SERVICE_ID_SELECTED, '$SERVICE_TIME')

Ejercicio del curso: lo que escribe el usuario va directamente a la cadena SQL; un código de producción usaría consultas parametrizadas.

salon.sh líneas 14–57

Raw: texto de salon.sh, líneas 14–57Repo: repositorio salon-appointment-scheduler en GitHub
  SERVICES=$($PSQL "SELECT service_id, name FROM services ORDER BY service_id")
  echo "$SERVICES" | while read SERVICE_ID BAR NAME
  do
    if [[ -n $SERVICE_ID ]]
    then
      echo "$SERVICE_ID) $NAME"
    fi
  done

  read SERVICE_ID_SELECTED

  if [[ ! $SERVICE_ID_SELECTED =~ ^[0-9]+$ ]]
  then
    MAIN_MENU "I could not find that service. What would you like today?"
    return
  fi

  SERVICE_NAME=$($PSQL "SELECT name FROM services WHERE service_id = $SERVICE_ID_SELECTED")
  if [[ -z $SERVICE_NAME ]]
  then
    MAIN_MENU "I could not find that service. What would you like today?"
    return
  fi
  SERVICE_NAME=$(echo $SERVICE_NAME | sed -E 's/^ *| *$//g')

  echo -e "\nWhat's your phone number?"
  read CUSTOMER_PHONE

  CUSTOMER_NAME=$($PSQL "SELECT name FROM customers WHERE phone = '$CUSTOMER_PHONE'")
  if [[ -z $CUSTOMER_NAME ]]
  then
    echo -e "\nI don't have a record for that phone number, what's your name?"
    read CUSTOMER_NAME
    INSERT_CUSTOMER_RESULT=$($PSQL "INSERT INTO customers(phone, name) VALUES('$CUSTOMER_PHONE', '$CUSTOMER_NAME')")
  fi
  CUSTOMER_NAME=$(echo $CUSTOMER_NAME | sed -E 's/^ *| *$//g')

  CUSTOMER_ID=$($PSQL "SELECT customer_id FROM customers WHERE phone = '$CUSTOMER_PHONE'")
  CUSTOMER_ID=$(echo $CUSTOMER_ID | sed -E 's/^ *| *$//g')

  echo -e "\nWhat time would you like your $SERVICE_NAME, $CUSTOMER_NAME?"
  read SERVICE_TIME

  INSERT_APPOINTMENT_RESULT=$($PSQL "INSERT INTO appointments(customer_id, service_id, time) VALUES($CUSTOMER_ID, $SERVICE_ID_SELECTED, '$SERVICE_TIME')")

Nivel de prueba: Prueba existente

Agenda de citas para una peluquería: las líneas de consulta del script · copiado el 2 de octubre de 2026 · sha256 5994d6b57c0e…

Pruebas

Las dos certificaciones Relational Database (un examen, y una certificación con 5 proyectos) y los dos repositorios públicos de los que salen los archivos de arriba.

Certificados

Repositorios