Bonus | Next generation loyalty system for everyone | Command Line Interface library

I dont get why do i need to use SELECT FROM SELECT, what does it give?

for example in this code

I had a problem.

When i create map in MongoDB Example Shop

Let's begin with a canonical example of Arc

I’m trying to setup the emulator so I can develop the firebase functions safely before deploying them. I just noticed that some REST calls I’m doing now fails - anybody know if it is not possible to use the REST feature of the RealTime DB https://firebase.google.com/docs/reference/rest/database

I'm trying to hit it with this URL

http://localhost:9000/?ns=-default-rtdb/development/DISHES.json

because this is what I set the firebaseConfig.databaseURL to (suggested here by Google)

Bonus info: If I try to do a GET to the URL via postman it creates another database called fake-server (http://localhost:4000/database/fake-server: null) 🤔

I'm trying to find a count embedded document keys across documents in a collection. For example:

I have an array of objects which is created on a button click. Now I have a scope variable that is assigned a default value.

This scope variable is part of textbox so now when user updates the textbox value that value is not getting automatically updated in all the records in bonus property of $scope.job.referralsrecords.

Code:

Edit: Turns out problem is at 15.line, i should have written counter-1 inside the brackets.

I should note that upcoming is a bonus question i have been asked for a new grad student level job so please only point out where am i making the mistake.

Hello, I'm trying to write a simple C code with this algorithm,

1. Enter a number
2. From a given list, try to imitate the number
3. Print out used numbers and the difference between given and immitated number
4. Also a rule about minimum and maximum value for the input

So I did this for the given task (it isn't done yet but my aim is not getting a problem within debugger for now);

I have a relatively simple case where:

1. My program will be receiving updates via Websockets, and will be using these updates to update it's local state. These updates will be very small (usually < 1-1000 bytes JSON so < 1ms to de-serialize) but will be very frequent (up to ~1000/s).
2. At the same time, the program will be reading/evaluating from this local state and outputs its results.
3. Both of these tasks should run in parallel and will run for the duration for the program, i.e. never stop.
4. Local state size is relatively small, so memory usage isn't a big concern.

The tricky part is that updates need to happen "atomically", so that it does not read from a local state that has for example, written only half of an update. The state is not constrained to using primitives and could contain arbitrary classes AFAICT atm, so I cannot solve it by something simple like using Interlocked atomic operations. I plan on running each task on its own thread, so a total of two threads in this case.

To achieve this goal I thought to use a double buffer technique, where:

1. It keeps two copies of the state so one can be read from while the other is being written to.
2. The threads could communicate which copy they are using by using a lock. i.e. Writer thread locks copy when writing to it; reader thread requests access to lock after it's done with current copy; writer thread sees that reader thread is using it so it switches to other copy.
3. Writing thread keeps track of state updates it's done on the current copy so when it switches to the other copy it can "catch up".

That's the general gist of the idea, but the actual implementation will be a bit different of course.

I've tried to lookup whether this is a common solution but couldn't really find much info, so it's got me wondering things like:

1. Is it viable, or am I missing something?
2. Is there a better approach?
3. Is it a common solution? If so what's it commonly referred to as?
4. (bonus) Is there a good resource I could read up on for topics related to this?

Pretty much I feel I've run into a dead-end where I cannot find (because I don't know what to search for) much more resources and info to see if this approach is "good". I plan on writing this in .NET C#, but I assume the techniques and solutions could translate to any language. All insights appreciated.

I have made a custom progress bar, consisting of three separete parts (a uniquely customisable center piece, a left part and a right part) but I'm having difficulty aligning the center block correctly in all phases.

First I will show the desired end state using three graphical layouts, then I will describe the current problem and finally I will provide my current workaround hack, which is faulty and needs a fix of some sort.

Three Desired States:
Desired outcome of a starting state showing 1% left aligned:

Desired outcome of halfway sate with center block perfectly in the middle at 50%:

Desired end sate with center block perfectly stopping at 100% right aligned: