title: How to validate data so no incorrect data is saved to the database, using javascript
body: <p>I would like to validate my code for adding a product to sqlite database, but dont know how I do that in the best way. I have been using this: </p>
  
  <p><code>routes.post('/product/', async (req, res)</code> </p>
  
  <p>and await for adding a product to the sqlite database, which was successful. 
  What I would like to accomplish is to check so the same product can't be added twice. Do you have any tips for how I can do that? 
  I was thinking if I could use an if statement to check that.. </p>