Implementation of callback in database request

Question

I am a complete beginner in JavaScript / Node.js / Express, but have some experience with php.

I am trying to pass data from a SQLite database to the console. In my previous attempts, console.log() was executed before the database got queried. Now I got it to work in the correct order with what I think is a callback, and I'm getting the data in the console.

Questions:

-Is this an actual callback?

-Is there a better (shorter / easier) way to "do this after that"?

-If I want to execute multiple functions in a certain order, would I want to end up with something like doThis(doThat(thenDoThis(finallyDoThat)));?

-If there's anything else about the code, feel free to review and comment.

// Some test code to get data from database

function getAllChampions(callback){
    db.all("SELECT * FROM champions", function(error, rows){
        if (error) console.log(error);
        return callback(error, rows);
    });
};

function showAllChampions(error, champions){
    if (error) console.log(error);
    else console.log('Champions: ' + JSON.stringify(champions));
};

getAllChampions(showAllChampions);

Mumin Korcan · Accepted Answer · 2017-08-10 21:51:47Z

If you run multiple async functions in a certain orderi it will look like something like this :

getData(function(a){  
    getMoreData(a, function(b){
        getMoreData(b, function(c){ 
            getMoreData(c, function(d){ 
                getMoreData(d, function(e){ 
                    ...
                });
            });
        });
    });
});

but it does not look nice and hard to control. Instead use promises, I recommend bluebirdjs library If you use nodejs, take it easy.

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