The callback error does not work and an exception error is generated! about node-sqlite

[theogravity]

I looked into this and there's actually two kinds of errors that can be thrown.

• At the function call level. This could be SQL parse or connection errors. This follows the [complete] parameter
• At the callback level. It's not clear what kind of errors are thrown at the callback level. This follows the [callback] parameter

The implementation properly follows the documented API:

https://github.com/TryGhost/node-sqlite3/wiki/API#databaseeachsql-param--callback-complete

I have updated the readme to clarify this further.

[NabiKAZ]

You said the implementation follows the original documentation.
But in this example you can see that exactly the same code calls the callback by the original project (db) but by this project (db2) an exception error is generated.

import sqlite3 from 'sqlite3';
var db = new sqlite3.Database('test.db');

import { open } from 'sqlite'
const db2 = await open({
  filename: 'test.db',
  driver: sqlite3.Database
});

db -> sqlite3 [original]

await db.each(
	'SELECT * FROM test WHERE score1 = ?', [1001],
	(err, row) => {
		console.log(">>> ERR:", err);
		console.log("row", row);
	}
);

result:

>>> ERR: [Error: SQLITE_ERROR: no such column: score1] {
  errno: 1,
  code: 'SQLITE_ERROR'
}
row undefined

db2 -> sqlite [this]

await db2.each(
	'SELECT * FROM test WHERE score1 = ?', [1001],
	(err, row) => {
		console.log(">>> ERR:", err);
		console.log("row", row);
	}
);

result:

node:internal/process/esm_loader:94
    internalBinding('errors').triggerUncaughtException(
                              ^

[Error: SQLITE_ERROR: no such column: score1] {
  errno: 1,
  code: 'SQLITE_ERROR'
}

Node.js v17.2.0

[theogravity]

Here's the implementation:

      this.db.each(
        sqlObj.sql,
        ...sqlObj.params,
         // [callback]
        (err, row) => {
          if (err) {
            return callback(formatError(err), null)
          }

          callback(null, row)
        },
        // [complete]
        (err, count) => {
          if (err) {
            return reject(formatError(err))
          }

          resolve(count)
        }
      )

If there is an error in the rows [callback], it's not going to reject the promise, but instead call the callback with the error populated. Your situation happens because it's a direct error (there are no rows to also return), so [callback] won't ever get called and so the error is thrown in the [complete] callback.

In your db -> sqlite3 [original] example, you have:

await db.each(
	'SELECT * FROM test WHERE score1 = ?', [1001],
	(err, row) => {
		console.log(">>> ERR:", err);
		console.log("row", row);
	}
);

• The native db.each() call is not a promise
• You're missing the completion callback, which is optional, so according to documentation, it looks like it combines the error into the row result

The core difference is sqlite is implementing the [complete] callback so it knows that the promise is to be resolved / rejected. Without it, it would not know when the call has finished returning rows and would make having .each() be a promise pointless.

[NabiKAZ]

I did not understand exactly what happened! But it does not matter! (:
My only goal was to see the difference in functionality between your version and the original version, which you seem to understand, and which seems normal.
Thanks.