UPDATE table1
Set col1 = something
FROM table1 as t
INNER JOIN table2 as t2 ON some condition
WHERE some conditionSELECT .... LIMIT 3. Эти три комментария не обязательно загружать AJAXом, лучше сразу при формировании страницы. А потом уже подгружать динамически, если пользователь захочет их прочитать 
$('#ajax').append(json);$('#ajax').append(json.id); 
"json": Evaluates the response as JSON and returns a JavaScript object. Cross-domain "json" requests are converted to "jsonp" unless the request includes jsonp: false in its request options.
$(document).on('click', function(event) {
var $target = $(event.target);
var $clickedForm = $target.closest('form').length > 0 ? $target.closest('form') : null;
if ($clickedForm)
$('form').not($clickedForm).remove();
else
$('form').remove();
});$(document).on('click', function(event) {
var $target = $(event.target);
var $clickedForm = $target.closest('form').length > 0 ? $target.closest('form') : null;
if ($clickedForm)
$('form').not($clickedForm).find('input[type="submit"]').remove();
else
$('form').find('input[type="submit"]').remove();
});
$i = false;
foreach ($arr as $key=>$val){
if($val["pid"]==0){
$i = $val["id"];
foreach ($arr as $k=>v){
if($v["pid"]==$i) $arr[$key]["children"]++;
}
}
}
$parent=array(
0 => 'text', 1 => 'text', 2 => 'text', 3 => 'text', 4 => 'text', 5 => 'text',
);
$children=array(
0 => array( 0 => "children text", 1 => "children text" ),
1 => array( 0 => "children text 2"),
....
);
foreach ($parent as $id=>$value){
$body.=' '.$value;
foreach ($children[$key] as $text){
$body.=' '.$text;
}
}
