How can I auto increment mysql LIMIT number? - php

Question

So I load 3 records with this msql query:
$query = "SELECT * FROM adatok ORDER BY `id` DESC LIMIT 3 "
And I created a load more button for user can be load the other 3 records with this query:
$query = "SELECT * FROM adatok ORDER BY `id` DESC LIMIT 4,3
And then come the problem.
Becouse when the user click for the load more button again, this get the same record as which had been received.
So how can I autoincrement limit number?
demo page:
http://neocsatblog.mblx.hu/addvideos/type.html
Press crtl+i for open box.
Update:
The id is auto incremented.
Thanks for the improvements for #spencer7593.
My table strukture looks like this.
Full php code, for what happening if you click the more button:
<?php
$connection = mysql_connect('localhost', 'neocsat_videos', 'password'); //The Blank string is the password
mysql_select_db('neocsat_videos');
mysql_query("SET CHARACTER SET utf8 ");
$page = 1
$query = "SELECT * FROM adatok ORDER BY `data_reg` DESC LIMIT 3,4 ";
$result = mysql_query($query);
while($row = mysql_fetch_array($result)){ //Creates a loop to loop through results
echo '<div class="video-header">';
if (!function_exists('echoOnce')) {
$runOnce = false;
function echoOnce()
{
global $runOnce;
if(!$runOnce)
{
$runOnce = true;
return "<img class='close2' src='/kep/icon_24x24_close_highlight.png'>";
}
}
}
$datatime=$row['date_reg'];
$img = '<img title="' . $datatime . '" src="time.png" class="time_icon" >';
echo echoOnce();
echo '<p>';
echo $row['name'];
echo '</p>';
echo $img;
echo '</div>';
echo '<div class="result">';
echo ' <iframe class="video" allowfullscreen style="overflow-x: hidden; overflow-y: hidden;" width="658px" height="569" frameborder="0" src="'.$row['url'].'"></iframe>' ;
echo '</div>';
echo '<div class="leiras">';
echo '<p>';
echo $row['leiras'] ; //$row['index'] the index here is a field name
echo '</p>';
echo '</div>';
echo '<div class="clear">';
echo '</div>';
?>
<a class='load'><div class='more'>További videók betöltése</div></a>
<?php
$connection = mysql_connect('localhost', 'neocsat_videos', 'zP77XRavaXMA'); //The Blank string is the password
mysql_select_db('neocsat_videos');
mysql_query("SET CHARACTER SET utf8 ");
$page = 1
$query = "SELECT * FROM adatok ORDER BY `data_reg` DESC LIMIT 3,4 ";
$result = mysql_query($query);
while($row = mysql_fetch_array($result)){ //Creates a loop to loop through results
echo '<div class="video-header">';
if (!function_exists('echoOnce')) {
$runOnce = false;
function echoOnce()
{
global $runOnce;
if(!$runOnce)
{
$runOnce = true;
return "<img class='close2' src='/kep/icon_24x24_close_highlight.png'>";
}
}
}
$datatime=$row['date_reg'];
$img = '<img title="' . $datatime . '" src="time.png" class="time_icon" >';
echo echoOnce();
echo '<p>';
echo $row['name'];
echo '</p>';
echo $img;
echo '</div>';
echo '<div class="result">';
echo ' <iframe class="video" allowfullscreen style="overflow-x: hidden; overflow-y: hidden;" width="658px" height="569" frameborder="0" src="'.$row['url'].'"></iframe>' ;
echo '</div>';
echo '<div class="leiras">';
echo '<p>';
echo $row['leiras'] ; //$row['index'] the index here is a field name
echo '</p>';
echo '</div>';
echo '<div class="clear">';
echo '</div>';
?>
<a class='load'><div class='more'>További videók betöltése</div></a>
<?php
}
mysql_close(); //Make sure to close out the database connection
?>
<meta charset="utf-8">
<link href='http://fonts.googleapis.com/css?family=Nunito:700' rel='stylesheet' type='text/css'>
<link href='http://fonts.googleapis.com/css?family=Lobster' rel='stylesheet' type='text/css'>
<link rel="stylesheet" type="text/css" href="style2.css">
<style>
#video-body,.video-body{
background-color:white;
width:780px;
position: fixed !important;
top: 100px;
right: -799px;
border-radius: 5px;
padding-left: 13px;
padding-bottom: 30px;
max-height: 453px;
overflow-x: hidden;
}
#video-header,.video-header{
border-bottom: 6px solid gray;
margin-left: 73px;
width: 628px;
}
#result,.result{
margin-left: 62px;
}
#video-header p,.video-header p{
margin-left: 158px;
font-family: 'Nunito', sans-serif;
font-size: 22px;
font-weight: bold;
padding-top: 12px;
margin-bottom: 11px;
}
#clear,.clear{
border-bottom: 6px solid gray;
width: 625px;
margin: 50px 82px;
}
#leiras, .leiras{
margin: -274px 139px 28px;
font-family: 'Nunito', sans-serif;
font-size: 13px;
font-weight: bold;
word-wrap: break-word;
background-color: rgba(0, 0, 0, 0.8);
border-radius: 5px;
min-height: 29px;
text-align: center;
padding: 3px;
}
.leiras p{
color:white;
}
</style>
<script>
$(".close2").click(function(){
$(".video-body").fadeOut();
$( "iframe" ).remove();
$( "div" ).remove();
$( "p" ).remove();
});
$(".video-body").on('click', '.load', function() {
jQuery.ajaxSetup({ async: false }); //if order matters
$.get("next.php", '', function (data) { $("#video-body").append(data); });
});
$( ".time_icon" ).tooltip({
show: null,
position: {
my: "left top",
at: "left bottom"
},
open: function( event, ui ) {
ui.tooltip.animate({ top: ui.tooltip.position().top + 10 }, "fast" );
}
});
</script>
<script>
// The plugin code
(function($){
$.fn.urlToLink = function(options) {
var options = $.extend({}, $.fn.urlToLink.defaults, options);
return this.each(function(){
var element = $(this),
expression = /(\b(https?|ftp|file|https|http):\/\/[-A-Z0-9+&##\/%?=~_|!:,.;]*[-A-Z0-9+&##\/%=~_|])/ig;
// The magic
return element.html( element.text().replace(expression, "<a class=lightview href='$1' target='"+options.target+"'>$1</a>") );
});
}
/**
* Default configuration
*/
$.fn.urlToLink.defaults = {
target : '_self' // Link target
}
})(jQuery)
// The call
$('p').urlToLink();
</script>
Javascript:
$(".video-body").on('click', '.load', function() {
jQuery.ajaxSetup({ async: false }); //if order matters
$( "#video-body" ).load( "next.php" );
});

Answer 1

$limit = 2; //how many items to show per page
$page = $_GET['page'];
if($page)
$start = ($page - 1) * $limit; //first item to display on this page
else
$start = 0; //if no page var is given, set start to 0
$sql = "SELECT column_name FROM tbl_name LIMIT $start, $limit";

Answer 2

$query = "SELECT * FROM adatok ORDER BYidDESC LIMIT ".($page*3 ).",3"; where $page is number of times that More button pressed.
on first click $page = 1, on second $page = 2 and so on

Answer 3

Assuming that id is unique, the normal pattern is to save the last id value retrieved by the previous query:
Then your "next" query would be of the form:
SELECT ... FROM adatok WHERE id < :last_id ORDER BY id DESC LIMIT 3
supplying the last retrieved id value for the :last_id placeholder.
For example, the previous query returns id values of 214, 212, 211. We "save" the value of 211 on the page. When the user clicks the "more data", then we take that value of 211, and supply it in the "next rows" query.
SELECT ... FROM adatok WHERE id < 211 ORDER BY id DESC LIMIT 3
^^^
This query is guaranteed to not return id values that were retrieved by the previous query. If the execution of this query returns id values of 210, 209, 208... we save that last retrieved id value, 208. A subsequent "next" query would use that saved value...
SELECT ... FROM adatok WHERE id < 208 ORDER BY id DESC LIMIT 3
^^^
And so on.
The OP "next" query is going to skip the fourth row; the first argument to LIMIT should be the number of rows retrieved previously... LIMIT 3,3. (Using LIMIT 4,3 as in the OP query is actually going to "skip" the fourth row.
For the next sets:
... LIMIT 6,3
... LIMIT 9,3
One of the issues with this approach is that if there are any insertions to the table with a larger id value, since the query is ordering by descending id value, a subsequent "next" query has the potential to return a row(s) that were retrieved previously. If rows with higher id values are deleted, this form has the potential to "skip" some id values.
Using a queries of the first form, at the top of my answer, results are unaffected by insertions/deletions of rows with higher id values.