Using Knex to Connect to PostgreSQL | 點燈坊

We can use Knex to connect to PostgreSQL; just install the Node-postgres library.

Version

Knex 0.95.11
Node-postgres 8.7.1
PostgreSQL 14.0

Add Library

$ yarn add knex pg

• knex：SQL builder to generate SQL
• pg：PostgreSQL library

Knex

import Knex from 'knex'

let knex = Knex ({
  client: 'pg',
  connection: {
    host: 'localhost',
    port: 5432,
    user: 'admin',
    password: '12345',
    database: 'DBLab'
  },
  searchPath: ['public']
})

let result = await knex ('articles').select ('*')
console.log (result)

Line 3

let knex = Knex ({
  client: 'pg',
  connection: {
    host: 'localhost',
    port: 5432,
    user: 'admin',
    password: '12345',
    database: 'DBLab'
  },
  searchPath: ['public']
})

Use Knex to connect to database :

• client: 'pg' : connect to PostgreSQL
• host：specify server
• port：specify port
• user：specify id
• password： specify password
• database：specify database
• searchPath：specify searching path, tables would be created under public

Line 15

let result = await knex ('articles').select ('*')
console.log (result)

Use Knex to generate SQL queries and return the result :

• knex : table for select

• select ：fields for select

Because Knex will return Promise, we have to use top-level await to deal with Promise.

Conclusion

• Just add Knex and pg library, change the client to pg, then you can connect to PostgreSQL by Knex