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Node.js - PostgreSQL Select last row
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In this article, we would like to show you how to select the last row in the Postgres database from Node.js level.
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: 'my_username',6
database: 'my_database',7
password: 'my_password',8
port: 5432,9
});10
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const fetchLastRows = async (count) => {12
const query = `13
SELECT * FROM "users"14
ORDER BY "id" DESC15
LIMIT $1;16
`;17
await client.connect(); // creates connection18
try {19
const { rows } = await client.query(query, [count]); // sends query20
return rows;21
} finally {22
await client.end(); // closes connection23
}24
};25
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fetchLastRows(1) // get only 1 row from the end of the table27
.then(result => console.table(result))28
.catch(error => console.error(error.stack));Result:
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┌─────────┬────┬───────┬─────────────────┬───────────┐2
│ (index) │ id │ name │ email │ country │3
├─────────┼────┼───────┼─────────────────┼───────────┤4
│ 0 │ 7 │ 'Nam' │ 'nam@email.com' │ 'Vietnam' │5
└─────────┴────┴───────┴─────────────────┴───────────┘create_tables.sql file:
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CREATE TABLE "users" (2
"id" SERIAL,3
"name" VARCHAR(100) NOT NULL,4
"email" VARCHAR(100) NOT NULL,5
"country" VARCHAR(15) NOT NULL,6
PRIMARY KEY ("id")7
);insert_data.sql file:
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INSERT INTO "users"2
("name", "email", "country")3
VALUES4
('Tom', 'tom@email.com', 'Poland'),5
('Chris', 'chris@email.com', 'Spain'),6
('Jack', 'jack@email.com', 'Spain'),7
('Kim', 'kim@email.com', 'Vietnam'),8
('Marco', 'marco@email.com', 'Italy'),9
('Kate', 'kate@email.com', 'Spain'),10
('Nam', 'nam@email.com', 'Vietnam');Native SQL query (used in the above example):
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SELECT * FROM "users"2
ORDER BY "id" DESC3
LIMIT 1;