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Node.js - PostgreSQL LIMIT
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In this article, we would like to show you how to use SQL LIMIT in Node.js.
Note: at the end of this article you can find database preparation SQL queries.
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const { Client } = require('pg');2
3
const client = new Client({4
host: '127.0.0.1',5
user: 'postgres',6
database: 'database_name',7
password: 'password',8
port: 5432,9
});10
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const fetchUsers = async (count) => {12
try {13
await client.connect(); // gets connection14
const { rows } = await client.query('SELECT * FROM "users" LIMIT $1', [count]);15
console.log(rows);16
} catch (error) {17
console.error(error.stack);18
} finally {19
await client.end(); // closes connection20
}21
};22
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fetchUsers(2); // LIMIT 2Output:
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[2
{ id: 1, name: 'John', role: 'admin' },3
{ id: 2, name: 'Chris', role: 'moderator' }4
]xxxxxxxxxx1
const { Client } = require('pg');2
3
const client = new Client({4
host: '127.0.0.1',5
user: 'postgres',6
database: 'my_database',7
password: 'password',8
port: 5432,9
});10
11
const fetchUsers = async (offset, count) => {12
const query = `SELECT * FROM "users"13
LIMIT $1 OFFSET $2`; 14
try {15
await client.connect(); // gets connection16
const { rows } = await client.query(query, [count, offset]); // sends queries17
console.log(rows);18
} catch (error) {19
console.error(error.stack);20
} finally {21
await client.end(); // closes connection22
}23
};24
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fetchUsers(1, 2); // LIMIT 2 OFFSET 1 Output:
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[2
{ id: 2, name: 'Chris', role: 'moderator' },3
{ id: 3, name: 'Kate', role: 'user' }4
]create_tables.sql file:
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CREATE TABLE "users" (2
"id" SERIAL,3
"name" VARCHAR(100) NOT NULL,4
"role" VARCHAR(15) NOT NULL,5
PRIMARY KEY ("id")6
);insert_data.sql file:
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INSERT INTO "users"2
("name", "role")3
VALUES4
('John', 'admin'),5
('Chris', 'moderator'),6
('Kate', 'user'),7
('Denis', 'moderator');