I am trying to do a very basic query from the explorer which looks like this:
var sensorFilter = [];
sensorFilter.push({
property_name: "uuid",
operator: "eq",
property_value: "1234"
});
var avg_sensor_pm = new Keen.Query("average", {
eventCollection: "status_update",
targetProperty: "sensors[0].properties[0].value",
filters: sensorFilter
});
The query returns nothing, I am wondering if the syntax to access indexed element in an array is not correct?
Anybody with the same problem?
The problem is that doing averages on values within an arrays is technically hard. I would recommend sending separate events for each status_update for each sensor and then doing an average on sensor.value.
You can definitely store arrays in Keen IO, but arrays of objects are not recommended. For more info: https://keen.io/docs/streams/data-modeling-guide/#arrays
Since I don't know anything about your data model, I should say that there might be other ways to do it too. Feel free to share it if the way I suggested wouldn't work for your use case.
Also this may be helpful: https://keen.io/docs/streams/data-modeling-guide-200/#avoid-trapping-your-data-lists
Related
I am trying to do string replace on entries of a column inside a db table. So far, I have reached till here:
$misa = DB::table('mis')->pluck('name');
for($i=0;;$i++)
{
$misa[$i] = substr_replace("$misa[$i]","",-3);
}
The error I am getting is "Undefined offset:443".
P.S. I am not a full-fledged programmer. Only trying to develop a few simple programs for my business. Thank You.
Since it's a collection, use the transform() collection method transform it and avoid this kind of errors. Also, you can just use str_before() method to transform each string:
$misa = DB::table('mis')->pluck('name');
$misa->transform(function($i) {
return str_before($i, ':ut');
});
There are a few ways to make this query prettier and FASTER! The beauty of Laravel is that we have the use of both Eloquent for pretty queries and then Collections to manage the data in a user friendly way. So, first lets clean up the query. You can instead use a DB::Raw select and do all of the string replacing in the query itself like so:
$misa = DB::table('mis')->select(DB::raw("REPLACE(name, ':ut' , '') as name"));
Now, we have a collection containing only the name column, and you've removed ':ut' in your specific case and simply replaced it with an empty string all within the MySQL query itself.
Surprise! That's it. No further php manipulation is required making this process much faster (will be noticeable in large data sets - trust me).
Cheers!
I want to filter and then sort my ember records such that the null records for a column are returned first. I'm not much familiar with ember and have a rails back ground.
filteredByData = myLeads.filterBy('status', 'open').filterBy('doNotCall', false).filterBy('phoneValid', true)
filtered = filteredByData.sortBy 'last_dialed_at', 'last_name', 'first_name', 'id'
Right now, my records are getting ordered according to the id.
What i want is to implement the NULLS LAST/FIRST from sql or postgres in any query (such a s SELECT * FROM t1 ORDER BY c1 DESC NULLS FIRST here in my sort so i get the records such that the last_dialed_atnull records come first.
I know the same can be implemented in rails like
Foo.order('last_dialed_at DESC NULLS FIRST') but i have no idea for same in Ember
Any help will be appreciated. Thanks in Advance.
P.S: I'll try to create a ember twiddle meanwhile to explain myself better.
Although you can resort to a SortableMixin/ArrayProxy, those are lower-level APIs than you should really need to use. sortBy works fine for a single value, but I generally use computed.sort when I need to sort multiple things. Take a look at the code and link in this answer https://stackoverflow.com/a/46788377/334913 they should get you going.
One of the common ways Ember suggests doing things is to do computed properties for each step (or set of steps) as it makes it far easier to reason about.
So I would do something along the lines of:
filteredLeads: Ember.computed('leads', function() {
return filteredResultsHere;
}),
sortDefinition: [], // put your entries from your SortableMixin here
sortedFilteredLeads: Ember.computed.sort('filteredLeads', 'sortDefinition'),
I solved my issue by using the Ember.SortableMixin instead of sortBy. I ended up with the following code and this worked perfectly for me.
leads = Ember.ArrayProxy.createWithMixins Ember.SortableMixin, content: filteredByData, sortProperties: ['lastDialedAt', 'firstName', 'lastName', 'id'], sortAscending: true
I'm not sure or much aware why this worked and the fundamentals to an extent that i can explain this behaviour. If there's any explanation for same from anyone, please feel free to put your answer below and i'll accept it as the answer.
Thanks
I'm still a bit lost when it comes to Sorted Sets and how to best construct them. Currently I have a simple set of activity on my site. Normally it will display things like User Followed, User liked, User Post etc. The JSON looks something like...
id: 2808697,
activity_type: "created_follower",
description: "Bob followed this profile",
body: null,
user: "Bob",
user_id: 99384,
user_profile_id: 233007,
user_channel_id: 2165811,
user_cube_url: "bob-anerson",
user_action: "followed this profile",
buddy: "http://s3.amazonaws.com/stuff/ju-logo.jpg",
affected: "Bill Anerson is following Jon Denver.",
created_at: "2014-06-24T20:34:11-05:00",
created_ms: 1403660051902,
profile_id: 232811,
channel_id: 2165604,
cube_url: "jondenver",
type: "profiles",
So if the activity type can be multiple things (IE Created Follow, Liked Event, Posted News, ETC) how would I go about putting this all in a sorted set? I'm already sure I want the score to be the created_ms but the question is, can I do multiple values in a sorted set that all have keys as fields? Should most of this be in a hash? I realize this is a fairly open question but after trying to wrap my head around all the tutorials Im just concerned about setting up the data structure before had so I dont get caught to deep in the weeds.
A sorted set is useful if you want to... keep stuff sorted! ;)
So, I assume you're interested in keeping the activities sorted by their creation time (ms). As for storing the actual data, you have two options:
Use the sorted set itself to store the data, even in native JSON format. Note that with this approach you'll only be able to fetch the entire JSON and you'll have to parse it at the client.
Alternatively, use the sorted to store "pointers" to hashes - i.e. the values will be key names in which you'll store the data. From your description, this appears the preferable approach.
In KnockoutJS, what's the proper way to update an observableArray of JSON data each time an AJAX command is run?
Right now, I'm blanking the array using something like viewmodel.items([]), then repopulating it with the JSON data from the server. Short of using the KnockoutJS mapping plugin (which might be the only way to do this) what is the correct path?
My server logic is going to send some of the same data each time, so I can't just iterate and push the items into the array unless I want duplicates.
//// Adding how I'm doing it today ////
I'm not sure why I'm doing it this way, but this is just how I initially figured out how to update. So basically, like I said before, I get JSON data, then I pass it to something like this:
_model.addIncident = function (json) {
var checked = json.UserTouches > 0 ? true : false;
_model.incidents.push({
id: ko.observable(json.IncidentIDString),
lastTouchId: ko.observable(json.UserLastTouchIDString),
weight: ko.observable(json.Weight),
title: ko.observable(json.Title),
checked: ko.observable(checked),
createdOn: ko.observable(json.IncidentCreatedOn),
servicename: ko.observable(json.Servicename),
inEdit: ko.observable(false),
incidentHistory: ko.observableArray(),
matchScore: ko.observable()
});
};
for each node in the JSON array. As you can see, I've got some custom observables in there that get build with every passing piece of data. Maybe this is the wrong way to go, but it's worked great up until now.
An observableArray is really just a normal observable with some extra methods for array operations.
So, if you want to set the value of an observableArray to a new array, you can just do:
viewModel.items(myNewArray)
The mapping plugin can help you update the existing items in an array with any updates. In this case, your UI will only be updated from any differences.
I know I'm way too late on this one as I found myself stuck in this situation just recently. We can use a simple Javascript util function as a work-around.
If you have already marked _model.incidents as observableArray, you can do something like this when binding the returned JSON data:
eval("_model.incidents("+JSON.stringify(json)+");");
It worked for me. Hope you have created your observable like this:
_model.incidents = ko.observableArray([]);
Most of the examples I've found deal with Linq to entities, which is not what I need. I have a standard DataTable which I need to modify before returning to the caller. I can iterate over the normal Table.Rows collection or do something like this with the new extension methods:
foreach (var x in table.AsEnumerable()) {
if (x.Field<int>("SomeField") > SomeValue)
x.SetField<string>("OtherField", "OtherValue");
}
But I'm still manually looping through the entire row collection. Not necessarily a big deal, but I'm wondering if there's a more elegant way to accomplish this with Linq somehow, in the sense that I need to create an expression that iterates over the results of a query and performs an arbitrary action, rather than just select elements from the container being enumerated.
I think what you're wondering is if there's some sort of extension method like
stuff.ForEach(x => x.Value = "new value");
Unfortunately, there is no such thing. When I began using LINQ to SQL, I wanted the same thing. But unfortunately, you must use a for loop.