MYSQL FOREIGN KEY

To create mysql foreign key the table engine must be InnoDB and the version is 5.
Command
------
CREATE TABLE `bookings` ( id INT , customer_id INT , FOREIGN KEY `customer_id` REFERENCES customer(id))ENGINE=INNODB;
ALTER TABLE `bookings` ADD CONSTRAINT FOREIGN KEY `customer_id` REFERENCES customer(id);

Highligt table row using Javascript

if(document.getElementById(id).hasChildNodes()){
var ctds = document.getElementById(id).getElementsByTagName('TD');
for(var chld = 0; chld < ctds.length ;chld++ ){
ctds[chld].className ='selectedFromList';
}
}
if(document.getElementById(id).parentNode){
var ctrs = document.getElementById(id).parentNode.getElementsByTagName('TR');
for(var chld = 0; chld < ctrs.length ;chld++ ){
if(ctrs[chld].id != id){
var ctds = ctrs[chld].getElementsByTagName('TD');
for(var chltr = 0; chltr < ctds.length ;chltr++ )
ctds[chltr].className = 'noteSelectedNorm';
}
}
}

Javascript email validation

function email_validation{
var email_reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
if(email_reg.test(email) == false){
showMessage('Invali email address!');
error = true;
}
}

Get Multiple Values in the select list using Javascript

function getMultipleSelectedValues(filed_name)
{
var selObj = document.getElementById(filed_name);
var selectedArray = new Array();
var countObj = selObj.options.length;
var arr_count = 0;
for(var i = 0 ; i < countObj ; i++)
if (selObj.options[i].selected) {
selectedArray[arr_count] = selObj.options[i].value;
arr_count++;
}
return selectedArray;
}

Create TRIGGER to back-up the old data

CREATE TRIGGER backup_feedback
BEFORE UPDATE ON feedbacks
FOR EACH ROW
BEGIN
IF OLD.feedback <> NEW.feedback THEN
INSERT INTO user_logs(tab_name,field_name,old_value,new_value) VALUES ('feedbacks','feedback',OLD.feedback,NEW.feedback);
END IF;
END;

Create Javascript array using PHP

$js_image_array = 'start script type=text/javascript \n var Aimage = new Array() \n var Aimage_descr = new Array();\n';

for( $i = 0; $i < count($L_ResultGraphics) ; $i++){
.$L_ResultGraphics[0]->file_name."=>".$L_ResultGraphics[0]->description."',";
$js_image_array = $js_image_array . "Aimage[$i] ='".$L_ResultGraphics[$i]->file_name."';\n";
$js_image_array = $js_image_array . "Aimage_descr[$i] ='".$L_ResultGraphics[$i]->description."';\n";
}
$js_image_array = $js_image_array . "\n script end";

print $js_image_array;