Firebase query dont display any data if data dont exist












0















Firebase query don't display any data if data don't exist no null no undefined , nothing no message at all , it only shows if it find something in the database.



  const ref =  this.fb.database().ref("Users");
var self = this;

ref.orderByChild('cellphone').equalTo('+351' + this.phoneNumber.toString()).on("child_added", (snapshot) => {
console.log(snapshot.val().cellphone);

if (snapshot.exists()){
let toast = self.toastCtrl.create({
message: 'Cellphone already exist',
duration: 2000,
position: 'bottom'
});

toast.present();
}

if(!snapshot.exists()){ // it dont even get here
console.log('can register');
}

});


My db structure, so if it does not find my cellphone does not shot nothing at all



my db










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  • 1





    Have you tried using "value" instead of "child_added" event? That is likely the issue here.

    – Burhan B
    Nov 20 '18 at 12:52











  • @BurhanB yep was the problem thanks sir

    – Kevin Dias
    Nov 20 '18 at 13:58
















0















Firebase query don't display any data if data don't exist no null no undefined , nothing no message at all , it only shows if it find something in the database.



  const ref =  this.fb.database().ref("Users");
var self = this;

ref.orderByChild('cellphone').equalTo('+351' + this.phoneNumber.toString()).on("child_added", (snapshot) => {
console.log(snapshot.val().cellphone);

if (snapshot.exists()){
let toast = self.toastCtrl.create({
message: 'Cellphone already exist',
duration: 2000,
position: 'bottom'
});

toast.present();
}

if(!snapshot.exists()){ // it dont even get here
console.log('can register');
}

});


My db structure, so if it does not find my cellphone does not shot nothing at all



my db










share|improve this question




















  • 1





    Have you tried using "value" instead of "child_added" event? That is likely the issue here.

    – Burhan B
    Nov 20 '18 at 12:52











  • @BurhanB yep was the problem thanks sir

    – Kevin Dias
    Nov 20 '18 at 13:58














0












0








0








Firebase query don't display any data if data don't exist no null no undefined , nothing no message at all , it only shows if it find something in the database.



  const ref =  this.fb.database().ref("Users");
var self = this;

ref.orderByChild('cellphone').equalTo('+351' + this.phoneNumber.toString()).on("child_added", (snapshot) => {
console.log(snapshot.val().cellphone);

if (snapshot.exists()){
let toast = self.toastCtrl.create({
message: 'Cellphone already exist',
duration: 2000,
position: 'bottom'
});

toast.present();
}

if(!snapshot.exists()){ // it dont even get here
console.log('can register');
}

});


My db structure, so if it does not find my cellphone does not shot nothing at all



my db










share|improve this question
















Firebase query don't display any data if data don't exist no null no undefined , nothing no message at all , it only shows if it find something in the database.



  const ref =  this.fb.database().ref("Users");
var self = this;

ref.orderByChild('cellphone').equalTo('+351' + this.phoneNumber.toString()).on("child_added", (snapshot) => {
console.log(snapshot.val().cellphone);

if (snapshot.exists()){
let toast = self.toastCtrl.create({
message: 'Cellphone already exist',
duration: 2000,
position: 'bottom'
});

toast.present();
}

if(!snapshot.exists()){ // it dont even get here
console.log('can register');
}

});


My db structure, so if it does not find my cellphone does not shot nothing at all



my db







javascript firebase firebase-realtime-database angularfire2






share|improve this question















share|improve this question













share|improve this question




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edited Nov 20 '18 at 14:09









KENdi

5,7792821




5,7792821










asked Nov 20 '18 at 11:36









Kevin DiasKevin Dias

406313




406313








  • 1





    Have you tried using "value" instead of "child_added" event? That is likely the issue here.

    – Burhan B
    Nov 20 '18 at 12:52











  • @BurhanB yep was the problem thanks sir

    – Kevin Dias
    Nov 20 '18 at 13:58














  • 1





    Have you tried using "value" instead of "child_added" event? That is likely the issue here.

    – Burhan B
    Nov 20 '18 at 12:52











  • @BurhanB yep was the problem thanks sir

    – Kevin Dias
    Nov 20 '18 at 13:58








1




1





Have you tried using "value" instead of "child_added" event? That is likely the issue here.

– Burhan B
Nov 20 '18 at 12:52





Have you tried using "value" instead of "child_added" event? That is likely the issue here.

– Burhan B
Nov 20 '18 at 12:52













@BurhanB yep was the problem thanks sir

– Kevin Dias
Nov 20 '18 at 13:58





@BurhanB yep was the problem thanks sir

– Kevin Dias
Nov 20 '18 at 13:58












1 Answer
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solution was using "value" instead of "child_added"



The child_added event fires for each matching child under the node that you query. If there are no matching children, it will not fire.



This means that to test whether a node exists, you must use a value handler. And since a query can have multiple results, you will need to loop over the children.






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    solution was using "value" instead of "child_added"



    The child_added event fires for each matching child under the node that you query. If there are no matching children, it will not fire.



    This means that to test whether a node exists, you must use a value handler. And since a query can have multiple results, you will need to loop over the children.






    share|improve this answer






























      0














      solution was using "value" instead of "child_added"



      The child_added event fires for each matching child under the node that you query. If there are no matching children, it will not fire.



      This means that to test whether a node exists, you must use a value handler. And since a query can have multiple results, you will need to loop over the children.






      share|improve this answer




























        0












        0








        0







        solution was using "value" instead of "child_added"



        The child_added event fires for each matching child under the node that you query. If there are no matching children, it will not fire.



        This means that to test whether a node exists, you must use a value handler. And since a query can have multiple results, you will need to loop over the children.






        share|improve this answer















        solution was using "value" instead of "child_added"



        The child_added event fires for each matching child under the node that you query. If there are no matching children, it will not fire.



        This means that to test whether a node exists, you must use a value handler. And since a query can have multiple results, you will need to loop over the children.







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Nov 20 '18 at 18:06

























        answered Nov 20 '18 at 14:27









        Kevin DiasKevin Dias

        406313




        406313






























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