I want to delete all rows with a specific name. In this example "gerda65".
I can delete one row by doing
mDatabase.child("shares")
.child("senneken-shares")
.child("1515596541713UjBPLm7rHMXGy6leFhj5H9VTQwh1")
.child("gerda65")
.removeValue();
But I want to delete all the gerda65 values under my "senneken-shares".
Here is my firebase db structure:
Does anyone how to do that?
Thank you in advance.
You can use Queries for that, since they allow proper data filtering. You would do something like:
var ref = mDatabase.child("shares")
.child("senneken-shares");
var query = ref.orderByChild("gerda65").equalTo(true);
This will return a list of all the "gerda65". So you need to add a listener to read this data, iterate through it, getting their keys and deleting them:
query.once('value', function(snapshot){
snapshot.forEach(function(snap){
ref.child(snap.key).remove();
});
});
Related
How do I delete data stored under a specific key in Firebase using Javascript? The key is generated by Firebase itself and I'm not sure how to reference to the specific key that I would like to delete.
The database is as below:
I would like to delete a specific child's data, in this case I would like to delete the child stored in the key: -LO1M0u_xW4MrolCTwrg
Here is my code:
function deleteComplaintPothole(){
var deleteComplaint= firebase.database().ref("complaintsPothole/complaintId");
deleteComplaint.remove();
document.getElementById("complaints").innerHTML='';
readComplaints();
}
Here is a screenshot of the website showing the complaints with its delete button:
Thanks #Marco Dal Zovo
Finally found the solution. Here is my code:
**
function deleteComplaintPothole(){
$(document).on('click', '.card-body', function(complaintsId){
var complaintsId = $(this).attr('data-complaint-id');
console.log(complaintsId);
var query = firebase.database().ref("complaintsPothole").orderByChild("complaintId").equalTo(complaintsId);
query.on('child_added', (snapshot) => {
snapshot.ref.remove();
window.location.reload();
});
});
}
**
As mentioned in the official Firebase Database Web guide:
Then, you could use orderByChild and equalTo like this:
firebase.database().ref('complaintsPothole').orderByChild('complaintId').equalTo('-LO1M0u_xW4MrolCTwrg').remove();
You can find more informations here: https://firebase.google.com/docs/database/web/lists-of-data
I have some data in a directory and I want to retrieve the value of a certain object e.g. Get the value of "NVR".
Another task I need to do is have a 'for' loop to go over and get information about different questions from the following data. I would need to get the number e.g. "001" and the items inside of that subdirectory. And it would also need to go through every directory in 'questions' such as NVR or MTH.
For the first one, you can try this:
firebase.database().ref().child("unique").on('value', function(snapshot) {
var datas = snapshot.val();
var nvr=datas.NVR;
)};
For the second one try this:
firebase.database().ref().child("questions").child("NVR").on('value', function(snapshot) {
snapshot.forEach(function(child) {
var keys=child.key;
var datas = child.val();
var correcta=child.val().correctAnswer;
var num=child.val().numberOfAnswers;
//etc
});
});
the first one the snapshot will be at unique, then you will be able to retrieve the child NVR.
In the second one, you iterate inside NVR and retrieve the key using var keys=child.key;
Try something like this for going through every directory in questions and for each one getting all the questions in it :
firebase.database.ref('questions').on('value').then((snapshots) => {
//print whole questions group (nvr, mth, etc)
console.log(snapshots.val())
snapshots.forEach((snapshot) => {
//print each question in question group
console.log(snapshot.val())
})
}
Both Peter's and Egor's answers load all data under unique. Since you know the key of the item whose value you want to retrieve, you can load this more efficiently with:
firebase.database().ref("unique/NVR").on('value', function(snapshot) {
var nvr=snapshot.val();
)};
My firebase db structure is given below,
users
fb-user-key1
user1-details1
Tags
Tag-key1
"name":"value"
Tag-key2
"name":"value"
fb-user-key2
user1-details2
Tags
Tag-key1
"name":"value"
Tag-Key1 & user-key's are generated by firebase with push(). firebase code to access the content is,
var fbref = firebase.database().ref("users");
fbref.child("Tags").on("child_added", function(e){
var Tagobj = e.val().name;
console.log(Tagobj);
});
This one is not returning anything. I am not able to access name:value pair in the above data structure.
`
adding modified code,
firebase.database().ref("users").on("child_added",function(e) { var Tagobj = e.val().Tags; });
Output of the above code is output data structure
How to access that name value pairs?? firebase keys are issue?
Not getting, where I am wrong. Appreciate your inputs.
Since Tags is a child property of each user, then you have to read it off of each user object.
If you want all Tags for all users, assuming Tags for each user is not updated after a user is created, you can do this:
tagsPerUserId = {};
firebase.datatabs().ref('users').on('child_added', function(snap) {
tagsPerUserId[snap.key] = snap.value().Tags;
// TODO: Notify view that tagerPerUserId is updated and needs to be re-rendered
console.log(`Tags for userId ${snap.key}: ${snap.value().Tags}`);
});
This way you will also get Tags of new users when they are created, but you will not get updates to Tags of existing users.
I am trying to access a specific product using its id from the below url,
https://tempstore.myshopify.com/products/1234.json
Its giving me 404 error.
Although, I am able to access all products as below:
https://tempstore.myshopify.com/products.json
I have to access the product which was just processed in checkout process.
I have its id as below:
var products = Shopify.checkout.line_items;
products will contain an array of product id's only which are processed in checkout.Now I need to access all other properties of these products.
I can surely do this:
https://tempstore.myshopify.com/admin/products/1234.json
But it requires Authentication.
Any thoughts?
From the frontend, you need to have the product handle to get the JSON object:
https://tempstore.myshopify.com/products/[handle].js
or
https://tempstore.myshopify.com/products/[handle].json
(Note that the returned values from the .js and .json endpoints are quite different from each other!)
Like you point out, the Shopify.checkout.line_items array of objects only has the product IDs, not the product handles. We're not completely out-of-luck, though, because we can get the entire list of products in the store including the product handles by hitting the /products.json endpoint.
Of course, this means grabbing a potentially huge JSON object just to get information that we should've had included in the checkout line items... but unless there's some alternate source of the line item information available on the checkout page, looping through the entire list may be what you need to do.
So your end code would look something like this:
Checkout.jQuery.getJSON( // Or whatever your preferred way of getting info is
'https://tempstore.myshopify.com/products.json',
function(prodlist){
for(var p = 0; p < prodlist.length; p++){
var prod = prodlist[p];
// Find if Shopify.checkout.line_items contains prod.id, left as exercise for the reader
if(found){
Checkout.jQuery.getJSON(
'https://tempstore.myshopify.com/products/' + prod.handle + '.js',
function(product){
/* Whatever needs to be done */
})
}
}
}
)
Hope this helps!
var shop = Shopify.shop;
var lineItems = Shopify.checkout.line_items;
var url = 'https://' + shop + '/products.json?callback=?';
var requiredData = [];
$.getJSON(url).done(function(data){
lineItems.forEach(function(lineItemProduct){
data.products.find(function(product){
if(lineItemProduct.product_id == product.id){
requiredData.push(product);
}
});
});
});
console.log(requiredData);
This is how I solved it, If it helps anybody :)
Reading the firebase doc this line:
database.ref('/').once('value').then(function(snapshot)
That is from a paragraph titled "Read data once" which I'm assuming reads in all the data from the database.
I'm just struggling to figure out how to assign data from the object that is returned to a variable in javascript.
What I want to do is populate a dropdown list with place names.
For instance if I have a field called Location in the db containing place names eg Sydney, Melbourne, Brisbane how would I get the data from the returned object and assign it a variable called place so I can then use the place variable to populate the html dropdown list.
You can try with this simple code -
database.ref('/').once('value').then(function(snapshot){
var list = snapshot.val();
if(list)
{
for (item in list)
{
itemIndex = item;
item = list[item];
//access your properties of the object say - item.location
}
}
});
You have to user 'child_added'
example:
var dbRef = firebase.database().ref().child('someChild');
dbRef.on('child_added', function(snap){
var res = snap.val().theValueYouNeed;
});
The code above gets the specific child in your db like this:
someChild:{
theValueYouNeed:"some value"
}
Then you can populate your list with the values.
I hope this helps!