自定义字段不会在vtiger中将数据插入数据库

I have created a custom field.

$field4 = new Vtiger_Field();     
$field4->name = 'PriceBook';    
$field4->label= 'Price Book';   
$field4->table = 'vtiger_account';   
$field4->column = 'pricebook_id';     
$field4->columntype = 'VARCHAR(100)';     
$field4->uitype = 10;     
$field4->typeofdata = 'V~O';     
$field4->helpinfo = 'Relate to an existing contact';     
$block->addField($field4);      
$field4->setRelatedModules(Array('PriceBooks'));

But this field doesn't submit any value to the database. what am I missing here.

Please check vtiger_account table in Database and check column pricebook_id exists in table. if not use the following code

// Turn on debugging level 
$Vtiger_Utils_Log = true;
include_once 'includes/Loader.php';
include_once('vtlib/Vtiger/Menu.php');
include_once('vtlib/Vtiger/Module.php');
$db = PearDatabase::getInstance();
$db->pquery("ALTER TABLE `vtiger_account` ADD COLUMN `pricebook_id` VARCHAR(100) NULL ;", array());