Hello 
Here is my erd and the below my creating table codes;
-- This script was generated by the ERD tool in pgAdmin 4. -- Please log an issue at https://redmine.postgresql.org/projects/pgadmin4/issues/new if you find any bugs, including reproduction steps.
BEGIN;
CREATE TABLE IF NOT EXISTS project1."Posts"
(
post_id serial NOT NULL,
user_id integer NOT NULL,
title "char" NOT NULL,
content text NOT NULL,
created_at timestamp with time zone NOT NULL,
PRIMARY KEY (post_id)
);
CREATE TABLE IF NOT EXISTS project1."Comments"
(
comment_id serial NOT NULL,
"post_id " integer NOT NULL,
"user_id " integer NOT NULL,
"text " text NOT NULL,
"created_at " timestamp with time zone NOT NULL,
PRIMARY KEY (comment_id)
);
CREATE TABLE IF NOT EXISTS project1.users
(
user_id serial NOT NULL,
username "char" NOT NULL,
password "char" NOT NULL,
email "char" NOT NULL,
PRIMARY KEY (user_id)
);
CREATE TABLE IF NOT EXISTS project1.products
(
"product_id " serial NOT NULL,
name "char" NOT NULL,
price numeric NOT NULL,
"category_id " integer NOT NULL,
PRIMARY KEY ("product_id ")
);
CREATE TABLE IF NOT EXISTS project1.orders
(
"order_id " serial NOT NULL,
user_id integer NOT NULL,
"order_date " date NOT NULL,
"total_amount " numeric NOT NULL,
PRIMARY KEY ("order_id ")
);
CREATE TABLE IF NOT EXISTS project1."order_items "
(
item_id serial NOT NULL,
order_id integer NOT NULL,
product_id integer NOT NULL,
quantity integer NOT NULL,
PRIMARY KEY (item_id)
);
CREATE TABLE IF NOT EXISTS project1.invoices
(
invoice_id serial NOT NULL,
order_id integer NOT NULL,
issued_date date NOT NULL,
amount_due numeric NOT NULL,
PRIMARY KEY (invoice_id)
);
CREATE TABLE IF NOT EXISTS project1.reviews
(
review_id serial NOT NULL,
product_id integer NOT NULL,
user_id integer NOT NULL,
rating integer,
comment text NOT NULL,
created_at timestamp with time zone NOT NULL,
PRIMARY KEY (review_id)
);
ALTER TABLE IF EXISTS project1."Posts"
ADD FOREIGN KEY (user_id)
REFERENCES project1.users (user_id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1."Comments"
ADD FOREIGN KEY ("post_id ")
REFERENCES project1."Posts" (post_id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1."Comments"
ADD FOREIGN KEY ("user_id ")
REFERENCES project1.users (user_id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1.orders
ADD FOREIGN KEY (user_id)
REFERENCES project1.users (user_id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1."order_items "
ADD FOREIGN KEY (order_id)
REFERENCES project1.orders ("order_id ") MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1.invoices
ADD FOREIGN KEY (order_id)
REFERENCES project1.orders ("order_id ") MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1.reviews
ADD FOREIGN KEY (product_id)
REFERENCES project1.products ("product_id ") MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
ALTER TABLE IF EXISTS project1.reviews
ADD FOREIGN KEY (user_id)
REFERENCES project1.users (user_id) MATCH SIMPLE
ON UPDATE NO ACTION
ON DELETE NO ACTION
NOT VALID;
END;
When I am trying to insert this data;
-- Dummy data for project1.users
INSERT INTO project1.users (username, password, email)
VALUES
('user1', 'pass123', '[email protected]'),
('user2', 'pass456', '[email protected]'),
('user3', 'pass789', '[email protected]'),
('user4', 'pass101', '[email protected]'),
('user5', 'pass202', '[email protected]');
-- Dummy data for project1."Posts"
INSERT INTO project1."Posts" (user_id, title, content, created_at)
VALUES
(1, 'Post Title 1', 'Content of post 1', NOW()),
(2, 'Post Title 2', 'Content of post 2', NOW()),
(3, 'Post Title 3', 'Content of post 3', NOW()),
(4, 'Post Title 4', 'Content of post 4', NOW()),
(5, 'Post Title 5', 'Content of post 5', NOW());
-- Dummy data for project1."Comments"
INSERT INTO project1."Comments" ("post_id ", "user_id ", "text ", "created_at ")
VALUES
(1, 2, 'Comment 1 on Post 1', NOW()),
(2, 3, 'Comment 2 on Post 2', NOW()),
(3, 4, 'Comment 3 on Post 3', NOW()),
(4, 5, 'Comment 4 on Post 4', NOW()),
(5, 1, 'Comment 5 on Post 5', NOW());
-- Dummy data for project1.products
INSERT INTO project1.products ("product_id ", "name ", "price", "category_id ")
VALUES
(1, 'Product 1', 10.99, 1),
(2, 'Product 2', 20.99, 2),
(3, 'Product 3', 15.99, 1),
(4, 'Product 4', 25.99, 2),
(5, 'Product 5', 12.99, 1);
-- Dummy data for project1.orders
INSERT INTO project1.orders ("user_id ", "order_date ", "total_amount ")
VALUES
(1, '2024-01-02', 50.99),
(2, '2024-01-03', 30.99),
(3, '2024-01-04', 45.99),
(4, '2024-01-05', 35.99),
(5, '2024-01-06', 22.99);
-- Dummy data for project1."order_items " Sql``` INSERT INTO project1."order_items " (order_id, product_id, quantity) VALUES (1, 1, 2), (2, 3, 1), (3, 5, 3), (4, 2, 2), (5, 4, 1);
-- Dummy data for project1.invoices
```sql
INSERT INTO project1.invoices (order_id, issued_date, amount_due)
VALUES
(1, '2024-01-03', 50.99),
(2, '2024-01-04', 30.99),
(3, '2024-01-05', 45.99),
(4, '2024-01-06', 35.99),
(5, '2024-01-07', 22.99);
-- Dummy data for project1.reviews
INSERT INTO project1.reviews (product_id, user_id, rating, comment, created_at)
VALUES
(1, 2, 4, 'Good product', NOW()),
(2, 3, 5, 'Excellent product', NOW()),
(3, 4, 3, 'Average product', NOW()),
(4, 5, 4, 'Very good product', NOW()),
(5, 1, 5, 'Outstanding product', NOW());
I keep getting this error;
ERROR: Key (user_id)=(1) is not present in table "users".insert or update on table "Posts" violates foreign key constraint "Posts_user_id_fkey"
ERROR: insert or update on table "Posts" violates foreign key constraint "Posts_user_id_fkey" SQL state: 23503 Detail: Key (user_id)=(1) is not present in table "users".
If anybody can help me with this I would be glad. I just want to remind that I am new to sql and thank you for your time!
