i am trying to call back a string in PHP JQUERY - php

I am trying to call back the value of content_columns to jquery.
PHP CODE:
if($act=="getcol"){
$pid=$_GET['pid'];
$domain_id = 1;
$PAGEresult = mysql_query("SELECT * FROM pages WHERE domain_id='$domain_id' AND id='$pid' ORDER BY id DESC");
$PAGErow = mysql_fetch_array($PAGEresult);
echo json_encode($PAGErow['content_columns']);
}
jQuery
$.get("get_actions.php?act=getcol&pid="+pid, function(data){
alert(data);
});
Can someone lead me down the right path please.

If by "same string" it is possible that it is cached. You can disable caching with jQuery's ajax library that you are using. You can also send a different query string such as with the system time to ensure you don't get a cached results. You can also use POST.
You will only ever get one result from that query. If you want multiple results, you need to iterate over mysql_fetch(). If you only want one result, add LIMIT 1 to your query. Otherwise it is incredibly wasteful. Finally, why use SELECT *? Use SELECT content_columns ..

Related

Retrieve constantly from database

I am doing this animation tool where I fetch a value from my database and then a picture will animate to a certain position. My question is if it is possible to retrieve data constantly or like every 5 seconds?
Somehow like this:
while(autoretreive){
$data = mysql_query("select * from ......");
}
UPDATED from here
Thanks for your answers! Made it a little bit clearer what to do! Maybe I can explain better what I'm doing in my code.
I am doing this animation program as said, where balls with information is moving around to different locations. I have one value that will be updated frequently in the database, lets call it 'city'.
First at previous page I post the balls of information I want based on the 'city' and I do like this (simplified):
$pid = $_POST['id'];
$pcity[0] = $_POST['city'];
$pcity[1] = $_POST['city'];
$pcity[2] = $_POST['city'];
//...
$while(autoretrieve) { // HOW TO?
$data = mysql_query(select * from table where city == $pcity[0] OR $pcity == [1] //...);
while($rows = mysql_fetch_array($data)){
$city = $rows['city'];
$id = $rows['id'];
if($city == example1){
"animate to certain pos"; //attached to image
}
else if($city == example2){
"animate to certain pos"; //attached to image
}
}
}
So for every update in the database the image will animate to a new position. So a time interval of 5 seconds would be great. I'm not an expert in coding so sorry for deprecated code. Not so familiar with AJAX either so what is going to be imported to the code? It is also important that the page is not reloading. Just the fetch from database.
you can do it with ajax and javascript
make one javascript function which contains ajax code to retrive data from database
and at your page load using setTimeout call your ajax function at every 5 second
You can use sleep function to control how often you want to fetch data.
while(autoretreive){
$data = mysql_query("select * from ......");
//output your data here, check more in link about server sent events bellow
sleep(5);
}
Since you haven't specified how you plan to access data I'm writing this answer assuming Server-Sent Events as they are only ones that make sense according to your question.
Now all this was according to your question which wasn't very clear on how do you plan to use data. Again you'll most likely want to fetch data using ajax, but Server Sent Events can also be a good way you could achieve this.
And don't use mysql_* it's deprecated, switch to PDO or mysqli_*

Showing progress bar while fetching data [duplicate]

I have this while loop, that basically loops through a lot of records in a database, and inserts the data in another:
$q = $con1->query($users1) or die(print_r($con2->errorInfo(),1));
while($row = $q->fetch(PDO::FETCH_ASSOC)){
$q = $con2->prepare($users2);
$q->execute(array($row['id'], $row['username'])) or die(print_r($con2-errorInfo(),1));
}
(The script has been shortened for easy reading - the correct one has a much longer array)
I would like to do this more graphical, and show a progress bar on how far it has went, instead of just seeing a page loading for a few minutes (there are ~20.000 rows in this one - I have tables with much more data)
I get that you could get the total number from the old database, and I could also easily put the current number into a variable like this:
$q = $con1->query($users1) or die(print_r($con2->errorInfo(),1));
$i = 0;
while($row = $q->fetch(PDO::FETCH_ASSOC)){
$q = $con2->prepare($users2);
$q->execute(array($row['id'], $row['username'])) or die(print_r($con2-errorInfo(),1));
$i++;
}
But now I need to actually fetch $i and display it - or something like it.
How is this "easily" done?
The code for the progress bar can either be in the same document as the while loop, or in another if easier.
You can do a "master" file that does an ajax to this first file to run a single query. You could get all the entry id's in this master file, and then pass it as a parameter to the second file that does a single query. Store these ids in a javascript array.
Create a function that does this, and when the first ajax is done, move to the second element of the id array, and do another ajax with a second parameter. That's how magento imports are done by the way :)
If you need further explanations, let me know, I tried my best to explain, but may have not been perfectly clear.
// you generate this javascript array using php.
// let's say you have all the ids that have to be processed in $Ids php array.
Ids = [<?php echo implode(',', $Ids); ?>];
function doAjax(i) {
$.ajax({ // using jquery for simplicity
'url': "ajax.php?id=" + Ids[i],
}).done(function(){
if ( i >= 0 ) {
// at the point you know you're at ((Ids.length-i)/(Ids.length) * 100) percent of the script
// so you can do something like this:
// $('.progressbar').css('width', ((Ids.length-i)/(Ids.length) * 100) + '%');
doAjax(i-1);
}
});
}
doAjax(Ids.length); // starting from the last entry
So, just to explain what this does. It starts by declaring a global javascript array that has all the ids that will need to be changed.
Then I declare a recursive ajax function, this way we can make sure that only one ajax runs at any single time (so the server doesn't blow up), and we can have a fairly accurate progress. This ajax function does the following:
Sends a request to ajax.php?id=xxx - where xxx is one of the ids in the javascript array.
In the file, we get the id ($_GET['id']), you take it from the old database, and insert it in the new one. This is only for one entry.
when the ajax is done, it goes to the done() function. Since we start the doAjax() function with the last element, we do the next iteration doAjax(i-1). Since we're going backwards in the array, we check if the key is positive. If it's not, the script will stop.
That's about it.
You can't. The php is first interpreted by the server and then send to the user as HTML-Code.
The only possibility would be creating a html-page and call the php-script with AJAX.

Progress bar while running while loop

I have this while loop, that basically loops through a lot of records in a database, and inserts the data in another:
$q = $con1->query($users1) or die(print_r($con2->errorInfo(),1));
while($row = $q->fetch(PDO::FETCH_ASSOC)){
$q = $con2->prepare($users2);
$q->execute(array($row['id'], $row['username'])) or die(print_r($con2-errorInfo(),1));
}
(The script has been shortened for easy reading - the correct one has a much longer array)
I would like to do this more graphical, and show a progress bar on how far it has went, instead of just seeing a page loading for a few minutes (there are ~20.000 rows in this one - I have tables with much more data)
I get that you could get the total number from the old database, and I could also easily put the current number into a variable like this:
$q = $con1->query($users1) or die(print_r($con2->errorInfo(),1));
$i = 0;
while($row = $q->fetch(PDO::FETCH_ASSOC)){
$q = $con2->prepare($users2);
$q->execute(array($row['id'], $row['username'])) or die(print_r($con2-errorInfo(),1));
$i++;
}
But now I need to actually fetch $i and display it - or something like it.
How is this "easily" done?
The code for the progress bar can either be in the same document as the while loop, or in another if easier.
You can do a "master" file that does an ajax to this first file to run a single query. You could get all the entry id's in this master file, and then pass it as a parameter to the second file that does a single query. Store these ids in a javascript array.
Create a function that does this, and when the first ajax is done, move to the second element of the id array, and do another ajax with a second parameter. That's how magento imports are done by the way :)
If you need further explanations, let me know, I tried my best to explain, but may have not been perfectly clear.
// you generate this javascript array using php.
// let's say you have all the ids that have to be processed in $Ids php array.
Ids = [<?php echo implode(',', $Ids); ?>];
function doAjax(i) {
$.ajax({ // using jquery for simplicity
'url': "ajax.php?id=" + Ids[i],
}).done(function(){
if ( i >= 0 ) {
// at the point you know you're at ((Ids.length-i)/(Ids.length) * 100) percent of the script
// so you can do something like this:
// $('.progressbar').css('width', ((Ids.length-i)/(Ids.length) * 100) + '%');
doAjax(i-1);
}
});
}
doAjax(Ids.length); // starting from the last entry
So, just to explain what this does. It starts by declaring a global javascript array that has all the ids that will need to be changed.
Then I declare a recursive ajax function, this way we can make sure that only one ajax runs at any single time (so the server doesn't blow up), and we can have a fairly accurate progress. This ajax function does the following:
Sends a request to ajax.php?id=xxx - where xxx is one of the ids in the javascript array.
In the file, we get the id ($_GET['id']), you take it from the old database, and insert it in the new one. This is only for one entry.
when the ajax is done, it goes to the done() function. Since we start the doAjax() function with the last element, we do the next iteration doAjax(i-1). Since we're going backwards in the array, we check if the key is positive. If it's not, the script will stop.
That's about it.
You can't. The php is first interpreted by the server and then send to the user as HTML-Code.
The only possibility would be creating a html-page and call the php-script with AJAX.

Search with PHP/MySQL and dynamically update with jQuery

I was wondering how to do the following best with PHP/MySQL and jQuery:
There is a basic search mask where you enter a city and a from-to-date. You process to the search-result page, where you then can narrow your search results with certain parameters (checkboxes, jQuery slider, text-input, ...). The search-results should then update on the fly without the whole page being reloaded...
I manage to use jQuery ajax and load to send information to another php file, perform e.g. a SELECT and return the results to the search detail page, but I don't know how to combine different changes that narrow the search results.
Furthermore, there are already results on the detail page, so I do not need to add more results but "delete" the results that do not fit anymore...
The thing is that each parameter to narrow the search is connected to another table in the database. Do I have to and how do I add joins to the original query...? Or am I thinking in the wrong direction?
Yes, this is absolutely the right direction. Use
$(document).ready(function() {
$('#ID_OF_YOUR_ELEMENT_TO_LOAD_INTO').load("load.php?parameter1=<?php echo $parameter1; ?>&parameter2=<?php echo $parameter2; ?>");
});
to get the results when the user gets on the page for the first time, to get the results according to your city and your dates.
Check in the load.php which parameters are set and use the ones that are set to build your query. Then, when the form (or forms, depending) are updated, you have to use .load again, like this:
$('#ID_OF_YOUR_FORM_BEING_UPDATED').change(function() {
$('#ID_OF_YOUR_ELEMENT_TO_LOAD_INTO').load("load.php?parameter1=<?php echo $parameter1; ?>&parameter2=<?php echo $parameter2; ?>&parameter3=<?php echo $parameter3; ?>");
});
Get the initial tuples via PHP/MySQL, save them into some Javascript structure and create the html needed to display the data with javascript from this structure.
Any time you want to filter the data you rewrite the html and check the filter condition on the fly, e.g. don't write tuples from the structure that don't match your filter condition.
You can see who this is done at http://www.wowhead.com
This is of course just one way. ;-)
You could always write some code to generate an SQL query based on passed arguments.
You ajax could query the page with a bunch of arguments in addition to your basic city and from-to date based on what the user has selected. If your page preserves the previous search options selected, it should be able to just let the user add on more options and keep processing them in the same way. Your php would then test to see if the arguments are set in the $_POST or $_GET variable ($_POST is more secure for ajax generally, but my example will use $_GET for simplicity) and build the query like that.
Example:
Javascript generates a query like searchAjaxHandler.php?city=Chicago&from=2012-03-01&to=2012-03-05&someColumnLowerRange=500&someColumnUpperRange=700
Your php script then processes as follows:
$query = "SELECT * FROM Data WHERE City=? AND Date > ? AND Date < ?";
$arguments = array($_GET['city'], $_GET['from'], $_GET['to']);
if (isset($_GET['someColumnLowerRange'])) {
$query .= " AND someColumn > ?";
$arguments[] = $_GET['someColumnLowerRange'];
}
if (isset($_GET['someColumnUpperRange'])) {
$query .= " AND someColumn < ?";
$arguments[] = $_GET['someColumnUpperRange'];
}
//execute the query
//using PDOs (google them...they are a good way to prevent sql injection and
//support multiple database types without modifying code too much), create a
//statement with the above query in put the statement in $statement
$statement->execute($arguments); //this uses the $arguments array to fill in the prepared statement's ?'s
//then do the stuff to get the retrieved rows out of the result returned
After all that, the javascript side would just to the same thing you were doing before by replacing all the previous results with the results that you got back.

Updating multiple page elements without refreshing the page using PHP & jQuery

I have a PHP page that uses jQuery to let a user update a particular item without needing to refresh the page. It is an availability update where they can change their availability for an event to Yes, No, or Maybe. Each time they click on the link the appropriate jQuery function is called to send data to a separate PHP file (update_avail.php) and the appropriate data is returned.
Yes
Then when clicked the params are sent to a PHP file which returns back:
No
Then, if clicked again the PHP will return:
Maybe
It all works fine and I'm loving it.
BUT--
I also have a total count at the bottom of the page that is PHP code to count the total number of users that have selected Yes as their availability by simply using:
<?php count($event1_accepted); ?>
How can I make it so that if a user changes their availability it will also update the count without needing to refresh the page?
My thoughts so far are:
$var = 1;
while ($var > 0) {
count($day1_accepted);
$var = 0;
exit;
}
Then add a line to my 'update_avail.php' (which gets sent data from the jQuery function) to make $var = 1
Any help would be great. I would like to stress that my main strength is PHP, not jQuery, so a PHP solution would be preferred, but if necessary I can tackle some simple jQuery.
Thanks!
In the response from update_avail.php return a JSON object with both your replacement html and your new counter value.
Or to keep it simple, if they click "yes" incriment the counter, if they click No or maybe and their previous action wasn't No or Maybe decrease the counter.
Assuming your users are logged into the system I'd recommend having a status field in the user table, perhaps as an enum with "offline", "available", "busy", "unavailable" or something similar and use the query the number of available users whilst updating the users status.
If you were to do this you'd need to include in extend your methods containing session)start() and session_destroy() to change the availability of the user to available / offline respectively
The best way is the one suggested by Scuzzy with some improvements.
In your php, get the count from the database and return a JSON object like:
{ count: 123, html: 'Yes' }
In your page, in the ajax response you get the values and update the elements:
...
success: function(data) {
$("#linkPlaceholder").html(data.html);
$("#countPlaceholder").html(data.count);
}
...

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