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Property of object inside indexedDB showing a value, when retrieved showing another

In chrome "Application" -> IndexedDB I see the property value of an object with value "inactive",
on retrieving that record, the property shows with value "active".
This is the function that does the retrieving:
function retrievesClientsFrom(databaseWithThisName, thisVersion, thisObjectStoreName) {
var requestToOpenDatabase = indexedDB.open(databaseWithThisName, thisVersion);
requestToOpenDatabase.onsuccess = function(event) {
var theDatabaseObject = requestToOpenDatabase.result;
//gets a transaction object
var theTransactionObject = theDatabaseObject.transaction(thisObjectStoreName, "readonly");
//gets the object store with that name
var theObjectStore = theTransactionObject.objectStore(thisObjectStoreName);
//gets all objects inside the objectStore sent to the function
var requestToGetContentOfAnObjectStore = theObjectStore.getAll();
requestToGetContentOfAnObjectStore.onsuccess = function(event) {
arrayOfRetrievedClients = requestToGetContentOfAnObjectStore.result;
//here I get the wrong value (I see it in chrome console).
console.log("arrayOfRetrievedClients: o%",arrayOfRetrievedClients);
};
};
requestToOpenDatabase.onerror = function(event) {
window.alert("There was a problem reading the database:
"+requestToOpenDatabase.error);
};
}
I have absolutely no idea what to do. Any ideas?

Get specifics ids in IndexedDB [duplicate]

I want to execute this query
select * from properties where propertyCode IN ("field1", "field2", "field3")
How can I achieve this in IndexedDB
I tried this thing
getData : function (indexName, params, objectStoreName) {
var defer = $q.defer(),
db, transaction, index, cursorRequest, request, objectStore, resultSet, dataList = [];
request = indexedDB.open('test');
request.onsuccess = function (event) {
db = request.result;
transaction = db.transaction(objectStoreName);
objectStore = transaction.objectStore(objectStoreName);
index = objectStore.index(indexName);
cursorRequest = index.openCursor(IDBKeyRange.only(params));
cursorRequest.onsuccess = function () {
resultSet = cursorRequest.result;
if(resultSet){
dataList.push(resultSet.value);
resultSet.continue();
}
else{
console.log(dataList);
defer.resolve(dataList);
}
};
cursorRequest.onerror = function (event) {
console.log('Error while opening cursor');
}
}
request.onerror = function (event) {
console.log('Not able to get access to DB in executeQuery');
}
return defer.promise;
But didn't worked. I tried google but couldn't find exact answer.

If you consider that IN is essentially equivalent to field1 == propertyCode OR field2 == propertyCode, then you could say that IN is just another way of using OR.
IndexedDB cannot do OR (unions) from a single request.
Generally, your only recourse is to do separate requests, then merge them in memory. Generally, this will not have great performance. If you are dealing with a lot of objects, you might want to consider giving up altogether on this approach and thinking of how to avoid such an approach.
Another approach is to iterate over all objects in memory, and then filter those that don't meet your conditions. Again, terrible performance.
Here is a gimmicky hack that might give you decent performance, but it requires some extra work and a tiny bit of storage overhead:
Store an extra field in your objects. For example, plan to use a property named hasPropertyCodeX.
Whenever any of the 3 properties are true (has the right code), set the field (as in, just make it a property of the object, its value is irrelevant).
When none of the 3 properties are true, delete the property from the object.
Whenever the object is modified, update the derived property (set or unset it as appropriate).
Create an index on this derived property in indexedDB.
Open a cursor over the index. Only objects with a property present will appear in the cursor results.
Example for 3rd approach
var request = indexedDB.open(...);
request.onupgradeneeded = upgrade;
function upgrade(event) {
var db = event.target.result;
var store = db.createObjectStore('store', ...);
// Create another index for the special property
var index = store.createIndex('hasPropCodeX', 'hasPropCodeX');
}
function putThing(db, thing) {
// Before storing the thing, secretly update the hasPropCodeX value
// which is derived from the thing's other properties
if(thing.field1 === 'propCode' || thing.field2 === 'propCode' ||
thing.field3 === 'propCode') {
thing.hasPropCodeX = 1;
} else {
delete thing.hasPropCodeX;
}
var tx = db.transaction('store', 'readwrite');
var store = tx.objectStore('store');
store.put(thing);
}
function getThingsWherePropCodeXInAnyof3Fields(db, callback) {
var things = [];
var tx = db.transaction('store');
var store = tx.objectStore('store');
var index = store.index('hasPropCodeX');
var request = index.openCursor();
request.onsuccess = function(event) {
var cursor = event.target.result;
if(cursor) {
var thing = cursor.value;
things.push(thing);
cursor.continue();
} else {
callback(things);
}
};
request.onerror = function(event) {
console.error(event.target.error);
callback(things);
};
}
// Now that you have an api, here is some example calling code
// Not bothering to promisify it
function getData() {
var request = indexedDB.open(...);
request.onsuccess = function(event) {
var db = event.target.result;
getThingsWherePropCodeXInAnyof3Fields(db, function(things) {
console.log('Got %s things', things.length);
for(let thing of things) {
console.log('Thing', thing);
}
});
};
}

indexeddb , how to use a cursor to update an array of objects

Question: How do I store a large array full of objects, all of which have 5 properties and all except the id property must be updated. Further more, why won't the code below work and how can I format it to work with the main question?
Info I've viewed:
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/openCursor
https://developer.mozilla.org/en-US/docs/Web/API/IndexedDB_API/Using_IndexedDB
https://developer.mozilla.org/en-US/docs/Web/API/IDBObjectStore/createIndex
Note: I am aware of the setInterval and its inefficiency, it is for testing purposes so I do not have to click many times to check for a result.
<html>
<body>
<script type="text/javascript">
let count =0;
let storeBuilt = false;
const dbName = "the_name";
let version=82;
let storeName= "store82";
let storeBuilding= false;
setInterval(build,1000/24);
function build(){
hello()
}
function hello(){
let customerData = [];
for(let i=0;i<=50000;i++){
customerData.push({name:"bob",minX:random(),minY:random(),maxX:random(),maxY:random(),id:random()})
}
let request = indexedDB.open(dbName, version);
request.onsuccess= function(event){
let db = event.target.result;
let transaction = db.transaction( storeName,"readwrite").objectStore(storeName);
if( storeBuilding=== false&& storeBuilt=== false){
storeBuilding= true;
let additem = addData(customerData, transaction);
additem.onsuccess= function(e){storeBuilt=true}
} else if (storeBuilt=== true){
let updateitem= updateData(customerData, transaction);
}
};
request.onupgradeneeded = function(event) {
let db = event.target.result;
// Create an objectStore to hold information about our customers. We're
// going to use "ssn" as our key path because it's guaranteed to be
// unique - or at least that's what I was told during the kickoff meeting.
let objectStore = db.createObjectStore(storeName, {keyPath:"names",autoIncrement:true});
objectStore.createIndex("name","name",{unique:true});
// Use transaction oncomplete to make sure the objectStore creation is
// finished before adding data into it.
objectStore.transaction.oncomplete = function(event) {
// Store values in the newly created objectStore.
let customerObjectStore = db.transaction(storeName, "readwrite").objectStore(storeName);
}
};}
function random (){
return (Math.floor((Math.random() * 10) + 1))
}
function addData(data,transaction){
return transaction.add(data)
}
function updateData(data,transaction){
let openCursor = transaction.index("name").openCursor();
openCursor.onsuccess= function(event){
let cursor = event.target.result;
if (cursor){
alert (cursor);
for(let I in data){
let item = data[I];
if(item.id === cursor.value.id){
let updateProperty = cursor.value;
updateProperty.minX = item.minX;
cursor.update(updateProperty);
cursor.continue()
}
}
}{alert("none")}
}
}
function deleteData(data,transaction){
}
</script>
</body>
</html>

Not sure if I understand the problem clearly, but generally you will want to load the objects from the object store, modify each object's properties, and then store the objects in the object store. There are several ways to do this. One way is to use cursor.update, but I don't think you need to do this at all. Just overwrite the objects.
function storeThings(db, things, callback) {
var txn = db.transaction('store82', 'readwrite');
txn.oncomplete = callback;
var store = txn.objectStore('store82');
for(var thing of things) {
store.put(thing);
}
}
function open(callback) {
var request = indexedDB.open();
request.onsuccess = _ => callback(request.result);
}
var things = [{id:1}, {id:2}, {id:3}];
open(db => storeThings(db, things, _ => console.log('done')));
I am using IDBObjectStore.prototype.put to store the objects. The put method will either create or overwrite an object in the store. It will create a new object in the store when no matching object is found based on the keypath. It will replace an existing object in the store when a matching object is found.
In your case, you are using ssn string as a keypath. So, in other words, it will create new people if ssn not found, or overwrite people if ssn found. You just need to make sure that the ssn property is defined within each person object you pass to put, or indexedDB will complain.

Redefine "this" within a function prototype and run it with new parameters

I have a function prototype that loads data from a path. The trick is that I need to change the path afterward. I tried call, apply, bind and even assign but as I am a novice I did not find the solution.
Here a sample of my code :
Chat.prototype.loadMessages = function() {
this.messagesRef = this.database;
var setMessage = function(data) {
var val = data.val();
this.displayMessage(data.key, val.name, val.text);
}.bind(this);
};
var chat = new Chat
function setPath (newpath) {
chat.loadMessages.messageRef = newpath; // I guess, it is where I'm wrong...
chat.loadMessages(); // It should load messages from the new path in my chat container.
}
As I said I also tried :
chat.loadMessages.call(newpath);
or
var setPath = function(newpath) {
chat.loadMessages(newpath);
}.bind(chat);
setPath();
chat.loadMessages();
But the chat container continues to disclose messages from the old path...

This looks a bit convoluted. Just pass messagesRef as a parameter and make it default to this.database:
Chat.prototype.loadMessages = function(messagesRef = this.database) {
// do whatever is needed with messagesRef
};
chat = new Chat();
chat.loadMessages(); // load from the default location
chat.loadMessages('foobar'); // load from this specific location

It looks like you are creating a function with loadMessages, which is fine but you need to pass in a value to set the new path. Is this more of what you were thinking?
Chat.prototype.loadMessages = function (newPath) {
this.messagesRef = newPath || this.database; // if newPath is empty than default to this.database
var setMessage = function(data) {
var val = data.val();
this.displayMessage(data.key, val.name, val.text);
};
var chat = new Chat
function setPath (newpath) {
chat.loadMessages(newpath);
}

Node/Javascript only send changed values

I'm writing a simple application where I send values to a mqtt broker given by a pot-meter (variable resistor). The thing I am trying to accomplish is that I only send changed values to save bandwidth. I am trying Object.observe, but that does not do anything. Can anybody help me?
My code:
var analogValue = 0;
every((0.5).second(), function() {
analogValue = my.sensor.analogRead();
var values = {values:[{key:'resistance', value: analogValue}]}
//another experiment here
var arr = ['resitance', analogValue];
Array.observe(arr, function(changes) {
console.log(changes);
});
arr[1] = analogValue
console.log('sent ',values,'to ',thingTopic)
client.publish(thingTopic, JSON.stringify(values));
});
var o = [analogValue];
Object.observe(o, function (changes) {
console.log(changes);
//eventually publish only changes to broker here
})
o.name = [analogValue]

You don't need to use Object.observe. You can just save the last measurement and check the new one against it. Like this:
// I'm assuming that any actual measurement will be different than 0
var lastMeasurement = 0;
every((0.5).second(), function() {
var analogValue = my.sensor.analogRead();
if (lastMeasurement !== analogValue) {
// the new value is different
var values = {values:[{key:'resistance', value: analogValue}]};
client.publish(thingTopic, JSON.stringify(values));
// update the last measurement value
lastMeasurement = analogValue;
}
});