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Add 1 in an sql field when a div is clicked [duplicate]

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Firing SQL query on click of button?
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I have a page where photos are uploaded, when you see the photos there is a button to give you points to the photo.
To the button I gave an onclick with a javascript function that has this php code
function puntos(){
<?php
mysql_query("UPDATE 'fotos' SET 'relevancia=relevancia+1' WHERE 'id = $id'");
?>
}
This is in photo.view.php in photo.php I have this code that retrieves the id of the selected photo
$id = isset($_GET['id']) ? (int)$_GET['id'] : false;
what am I doing wrong?

You're far from home.
Back to basics first:
Server vs. client
mysql and PHP run on the server
JavaScript runs on the client in their browser.
This means javascript cannot access your database directly, you need to do a lot of work before you get there.
Detecting and reacting on a click is something JavaScript can do (and is quite adept at doing).
Communication
Normally when a page downloads it and the components it refers are sent from the server to the client over HTTP.
Once in the browser, to get something back from the client to the server the only way is to send another query or open up some network connection somehow from the client to the server which then transfers that content, or indicates somehow what happened on the client.
Traditionally this meant a form and a click resulting in a GET or POST HTTP request and a reload of the page in the browser.
That's till we got:
AJAX
Essentially the connection from the client to the server can also be initiated by JavaScript itself and it can talk to a server component (just like the browser can) without having to reload a page or having to submit a form or so). This allows one to create things where a click or even a move of the mouse (or anything else JavaScript can detect -it can detect a lot-) can result into data being sent to the server and answers collected by that JavaScript. If it updates the page (aka DOM) is up to the script to chose.
Server Side
Now having JavaScript on the client communicating with the server still isn't going to let said JavaScript update a database. So you need a sever side component that does stringent validations (the code you have above is a horror story from the security side should that ever get to work) and updates a database behind it as needed.
TL;DR
Suggest you read up more on how to do simple AJAX
Some starting points:
https://www.w3schools.com/xml/ajax_intro.asp
https://www.owasp.org/index.php/AJAX_Security_Cheat_Sheet
But there's much more out there for sure.

How can I run a method asynchronously in Google Apps Script?

I have a function that's called by the client when some data is submitted via a form. This triggers an action that sends an email out to individuals that wish to receive notifications. The problem is that this has to be done synchronously with the form submit, so the user submitting the form has to wait for the emails to be sent before they receive the return data from Apps Script saying that the submission was successful.
This can sometimes take several seconds. Is there a way to asynchronously run a function in apps script (So the server can return a message to the client while the emails are being sent)?
Or even better, create an event that I can listen to similar to events in .NET?

Your title is misleading. you don't want it to run async, which it will by default when you make a call like google.script.run.somefunction() from the client side.
What you need to do is, create another function within the apps script, (say EmailSentSuccessfully()), which reports true/false based on whether the email has finished sending. It could read a 'Property' (essentially a static global variable) which is updated by the function that actually sends the email. You call EmailSentSuccessfully() from your client, say every 2 seconds, till it returns a true value. Till that time, do nothing, (or disable form elements so the user cannot take any other action).

How to pass javascript variables to rails variables

How can I pass a javaScript variable into ruby. I want to do something like this but I don't know how to express it.
function save(){
var g = document.getElementById("self").value;
<% #owner.info = g %>
}
Another possible work around is that i would need to be able to extract contents of a text area through rails and not javascript.
Can anyone help me?

What you are attempting to do doesn't make sense with a vanilla rails installation and javascript. Here's a good workflow that accomplishes what you're trying to do along with some details:
1. A page is requested from the server
The ruby code that runs rails and your application is executed on the server. The server receives a request, executes the ruby code, and sends the response as an html document.
2. A user gets the response from the server
The user's browser receives the html and turns it into a pretty web page. It's at this point that any javascript related to your application is executed in the user's browser. The connection with the server has been severed and no further ruby code will be executed until another request is made.
3. The user fills out an ajax form
On the page rendered in step 2, you have a form. Following this guide you can tell this form to submit via ajax. That means instead of requesting a new web page, the browser will send a special request using javascript to the server. The server can save the form values to your database and send a response back to the browser. All the while the user hasn't left the page they are currently viewing.
Alternatively you can skip the ajax and have the user submit the form, but you'll need to redirect them back to the page they were viewing (and probably adding a note the form they submitted was saved).

passing arguments to python function by javascript

Since mostly a backend guy, I am not sure how can I achieve the following since it
requires some interaction with the browser.
So, I have a the following things so far.
A communication protocol where server is in python and client is in javascript code.
Ultimately, I want my data to reach to that javascript code.
Now, this data is being captured from browser.
As a practice.. what I am trying to do is.. have two radio buttons on my browser and a submit button
*radio A
*radio B
* Submit
Now, when the user presses submit, I somehow want to create a query "user submitted: A (or B)" and this query i am able to capture on python script.
I am at lost on how to do this.
My guess is that "submit" invokes a python script.
But what if my python server is always on .. how do i parse that response from the click of browser to this python server?

This is the way it usually works:
Client (browser) visits webpage and initiates request to server
Server (in your case, Python) handles request and writes HTML response, including the radio-button form
Client fills out form and hits Submit, triggering another request to the server
Server handles the second request and writes another response (e.g. "Purchase successful", "message posted", etc.).
Note that the second request is a brand-new request. You may want some way of linking the first request to the second one unless the second request is anonymous. Some frameworks will do that for you, but if you are making the server from the ground up you'll want some kind of session mechanism to keep track of state.
To get the client to make the second request, the simplest is to add appropriate action and method attributes to the form element in your HTML. action specifies the URL to access for the form request, and method is either GET or POST. (More advanced usage, e.g. on this site, typically uses AJAX to make the submissions instead).

How to make auto-updating (ajax) counter correctly? Or how to disable network log?

I'm trying to make auto-reload counter (for ex.: Messages [num]).
So, I just in setTimeout(); getting JSON code from test_ajax.php. I think it's not correctly..
Can I send info by server (I think not, but suddenly I something don't know..)?
Why I think that's not correctly: because when I'm looking in my chrome network log (F12 -> network tab), I see a lot of requests (to test_ajax.php), but when, I'm visiting vk.com (great example for ajax) or facebook.com, I don't see any requests while something will not change.
So, what's incorrectly in my solution (or what's bad..)?
UPD: Sorry, vk.com sending requests to q%NUM%.queue.vk.com every 25s, but until 25s last request's status is "Pending". When someone, for example, sending me a message it immediately display it. And request has parameter "wait" which equals 25. This delay in requests doing on server side.. But how?

Ajax counter can be done in easy just include below files
index.html
counter.php (ajax file)
necessary images
JS file (for jquery paging call)
download link: https://docs.google.com/open?id=0B5dn0M5-kgfDcE0tOVBPMkg2bHc

What you are looking for is called COMET (also sometimes called Reverse AJAX) techniques.
Doing what you want to do, e.g. regular polls, is one way of doing it.
A lot is actually happening on the server side; to avoid recreating new connections on every poll, some servlet containers like Jetty started to implement techniques like Continuation which basically maintain a two-way connection open.
In the Java world, with Servlet 3, you have asynchronous calls as part of the specs.