Passing results out of NodeJS database function to use outside of it

Question

I have the following code I am using with a SQLite3 npm module.

db.all("SELECT * FROM posts WHERE id = '3', function(err, rows) {
   return rows
})

I would like to access the data from rows outside of this code, for example...

db.all("SELECT * FROM posts WHERE id = '3', function(err, rows) {
   return rows
}) 

// >>> *** I want to call the results for rows here ***

Could someone explain with a quick example how this is done?

Answer 1

You can make a use of promises, for example:

new Promise(function (resolve, reject) {
  db.all("SELECT * FROM posts WHERE id = '3', function(err, rows) {
    // Check if there's an error, if it exists the promise will end up.
    if (err) {
      reject(err)
      return
    }

    resolve(rows)
  })
}).then(function (rows) {
  // You can make use of your code here
}).catch(function (err) {
  console.log(err)
})

Promises act asynchronously so it will be resolved once the data is readed from your db.

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