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Ordering directly on JSONField is not yet supported in Django. But it's possible via RawSQL using PostgreSQL functions for jsonb: from django.db.models.expressions import RawSQL RatebookDataEntry.objects.all().order_by(RawSQL("data->>%s", ("json_objects_key",))) This e...

Some examples for a window of size 3: ;; Naïve attempt: (loop for (first second third) on '(1 2 3 4 5) do (print (* first second third))) ;; prints 6 24 60 then Errors on (* 4 5 NIL) ;; We will try again and put our attempt into a function (defun loop-3-window1 (function list) (loop...

Sometimes for organizational or other reasons it makes sense to have your top level resource return a sub-resource that would look like this. (Your sub-resource does not need to be an inner class) import javax.ws.rs.GET; import javax.ws.rs.Path; import javax.ws.rs.Produces; @Path("items&q...

package com.example.xml.adapters; import javax.xml.bind.annotation.adapters.XmlAdapter; public class StringTrimAdapter extends XmlAdapter<String, String> { @Override public String unmarshal(String v) throws Exception { if (v == null) return null; ...

There are two PyCharm editions: Community and Professional. Both are downloadable from JetBrains website. Additionally, there is another edition, PyCharm Edu. JetBrains recommend this edition, if you are learning or teaching Programming with Python. The supported platforms are Windows, Linux and m...

Microsoft Access has existed since 1992, and older versions continue to see regular use when business-critical database applications have been built on them. A very comprehensive resource summarizing the release history (with links to release notes, where available) is: Microsoft Access Version...

.my-div { width: 300px; height: 200px; background-size: 100%; background-repeat: no-repeat; background-image: linear-gradient(to right, black 0%,white 100%), url('https://static.pexels.com/photos/54624/strawberry-fruit-red-sweet-54624-medium.jpeg'); background-blend-mod...

A common thought pattern for inexperienced Java programmers is that exceptions are "a problem" or "a burden" and the best way to deal with this is catch them all1 as soon as possible. This leads to code like this: .... try { InputStream is = new FileInputStream(fileName);...

<dom-module id="using-listeners-obj"> <template> <style> :host{ width: 220px; height: 100px; border: 1px solid black; display: block; } #inner{ width: calc(100% - 10px); height: 50px; ...

Another way to add an event listener is to use on-event annotation in DOM. Below is an example using up event, which is fired when finger/mouse goes up <dom-module id="annotated-listener"> <template> <style> .inner{ width: calc(200px); he...

You can also fire your own events and then listen to them from either Polymer element of HTML page This Element fires the custom event <dom-module id="custom-event"> <template> <style> #inner{ width: 200px; height: 50px; bor...

Properties with notify:true also fires an event <link rel="import" href="../bower_components/paper-input/paper-input.html"> <dom-module id="property-change-event"> <template> <style></style> <paper-input id="input&quo...

To search for text foo within a {} block surrounding the cursor use the following command (<ESC> - escape key, <CR> - enter key) : vi{<ESC>/\%Vfoo<CR> now you can jump between the matches within the block by pressing n and p. If you have hlsearch option enabled this will ...

As a privileged user (root or sudo): Create scollector directory: mkdir /opt/scollector In the /opt/scollector directory, download the latest binary build from the bosun/scollector site, [http://bosun.org/scollector/][1] wget https://github.com/bosun-monitor/bosun/releases/download/"version...

The Runnable interface defines a single method, run(), meant to contain the code executed in the thread. The Runnable object is passed to the Thread constructor. And Thread's start() method is called. Example public class HelloRunnable implements Runnable { @Override public void run()...

Detailed instructions on getting datepicker set up or installed.

Almost any MPI call returns an integer error code, which signifies the success of the operation. If no error occurs, the return code is MPI_SUCCESS: if (MPI_Some_op(...) != MPI_SUCCESS) { // Process error } If an error occurs, MPI calls an error handler associated with the communicator, ...

An example of a class that contains a parcelable class inside: public class Repository implements Parcelable { private String name; private Owner owner; private boolean isPrivate; public Repository(String name, Owner owner, boolean isPrivate) { this.name = name; ...

get-childitem | foreach-object { if ($_.IsReadOnly) { return } } Pipeline cmdlets (ex: ForEach-Object, Where-Object, etc) operate on closures. The return here will only move to the next item on the pipeline, not exit processing. You can use break instead of return if you want to exit processing...

Inspired by PowerShell: Function doesn't have proper return value function bar { [System.Collections.ArrayList]$MyVariable = @() $MyVariable.Add("a") | Out-Null $MyVariable.Add("b") | Out-Null $MyVariable } The Out-Null is necessary because the .NET ArrayLis...