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Node.js - PostgreSQL - select first N rows
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In this article, we would like to show you how to select the first N rows in the PostgreSQL database usingΒ Node.js.
Note:Β at the end of this article you can find database preparation SQL queries.
const { Client } = require('pg');
const client = new Client({
host: '127.0.0.1',
user: 'postgres',
database: 'database_name',
password: 'password',
port: 5432,
});
const fetchUsers = async (count) => {
try {
await client.connect(); // gets connection
const { rows } = await client.query('SELECT * FROM "users" LIMIT $1', [count]);
console.table(rows);
} catch (error) {
console.error(error.stack);
} finally {
await client.end(); // closes connection
}
};
fetchUsers(3); // fetch first 3 rows
Result:Β
βββββββββββ¬βββββ¬ββββββββββ¬ββββββββββββββββββββ¬βββββββββββ
β (index) β id β name β email β country β
βββββββββββΌβββββΌββββββββββΌββββββββββββββββββββΌβββββββββββ€
β 0 β 1 β 'Tom' β 'tom@email.com' β 'Poland' β
β 1 β 2 β 'Chris' β 'chris@email.com' β 'Spain' β
β 2 β 3 β 'Jack' β 'jack@email.com' β 'Spain' β
βββββββββββ΄βββββ΄ββββββββββ΄ββββββββββββββββββββ΄βββββββββββ
Database preparation
create_tables.sql
Β file:
CREATE TABLE "users" (
"id" SERIAL,
"name" VARCHAR(100) NOT NULL,
"email" VARCHAR(100) NOT NULL,
"country" VARCHAR(15) NOT NULL,
PRIMARY KEY ("id")
);
insert_data.sql
Β file:
INSERT INTO "users"
("name", "email", "country")
VALUES
('Tom', 'tom@email.com', 'Poland'),
('Chris', 'chris@email.com', 'Spain'),
('Jack', 'jack@email.com', 'Spain'),
('Kim', 'kim@email.com', 'Vietnam'),
('Marco', 'marco@email.com', 'Italy'),
('Kate', 'kate@email.com', 'Spain'),
('Nam', 'nam@email.com', 'Vietnam');
Native SQL query (used in the above example):
SELECT *
FROM "users"
LIMIT 3 -- LIMIT N