Create a table with a interget PK. CREATE TABLE entries ( id SERIAL PRIMARY KEY NOT NULL, title VARCHAR(255) NOT NULL, type VARCHAR(255) NOT NULL, value FLOAT NOT NULL, created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL ); DROP TABLE entries; Create Entry INSERT INTO entries (title, value, type) VALUES ('Groceries 1', 200.00, 'expense'); database.js const { Pool } = require("pg"); const db = new Pool({ user: "postgres", password: "postgres", host: "localhost", port: 5432, // default Postgres port database: "budgetapp", }); module.exports = db;