Error: Cannot find module 'pg', after running npm install pg

Question

Using VSCode. Installed latest Node.js (first time user) for Windows, and the desired modules, one of which was 'pg' (npm install pg)

At the top of my script I have this: const pg = require('pg');

When i attempt to debug, I get this error when it hits that line:

Exception has occurred: Error
Error: Cannot find module 'pg'
at Function.Module._resolveFilename (module.js:547:15)
at Function.Module._load (module.js:474:25)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at Object.<anonymous> (c:\EBI\Work\Node-pg-log\get_pg_log.js:3:12)
at Module._compile (module.js:649:14)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)

Is there something else I need to install or set up? Debugging is in place.

Canned

Is it only when debugging is in place, and only that module? Just trying to get a sense of the situation. – Mongeau

Happens in regular run mode as well. And it seems to be all modules I'm trying to use. – Canned

do you have node_modules folder in your project root? – Wainscoting

Answer 1

This usually happens when node_modules/ folder is located in some sub-directory. Like

/app
----index.js
----/libs
--------/node_modules/

You want a directory structure like

/app
----index.js
----node_modules/

Where node_modules folder is either in the current directory or in some upper level directory

Aura

Answer 2

If you are using TypeScript it is necessary to install pg types. Use the command

npm install --save-dev @types/pg

Retarder

its not about pg type, this commands help me "npm install pg --save" – Brigand

Answer 3

We had the same issue with Strapi 4, we fixed it by installing pg:

If you get a “cannot find module ‘pg’” error, install it by running yarn add pg or npm install --save pg

As written here: https://strapi.io/blog/postgre-sql-and-strapi-setup

Churchwell