Magento 1 how to add a attribute in all attribute set and specified group

Many merchant have multiple attribute sets. Some times they have to add single attribute to all sets. Default magento does not have to do automatically. Either you can use any custom plugin to do it or some custom script.

You can use below script to achieve it.

<?php 

$code = @$_GET['code'];
if(!$code){
    print "Please enter code";
    die;
}

$groupKey = @$_GET['group'];
if(!$groupKey){
    $groupKey = 'General';
}

set_time_limit(0);
require("../app/Mage.php");

Mage::init('admin');
Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);

$attSet = Mage::getModel('eav/entity_type')->getCollection()->addFieldToFilter('entity_type_code','catalog_product')->getFirstItem(); // This is because the you adding the attribute to catalog_products entity ( there is different entities in magento ex : catalog_category, order,invoice... etc )
$attSetCollection = Mage::getModel('eav/entity_type')->load($attSet->getId())->getAttributeSetCollection(); // this is the attribute sets associated with this entity

$attributeInfo = Mage::getResourceModel('eav/entity_attribute_collection')->setCodeFilter($code)->addFieldToFilter("entity_type_id", $attSet->getId())->getFirstItem();
$attCode = $attributeInfo->getAttributeCode();
$attId   = $attributeInfo->getId();

foreach ($attSetCollection as $a)
{
  $set   = Mage::getModel('eav/entity_attribute_set')->load($a->getId());
  $setId = $set->getId();
  $group = Mage::getModel('eav/entity_attribute_group')->getCollection()->addFieldToFilter('attribute_set_id',$setId)
                 ->addFieldToFilter('attribute_group_name', $groupKey)->setOrder('attribute_group_id',"ASC")->getFirstItem();
  $groupId = $group->getId();
  
  $newItem = Mage::getModel('eav/entity_attribute')->getCollection();
  $newItem->addFieldToFilter("entity_type_id", $attSet->getId());
  $newItem->addFieldToFilter("attribute_id", $attId);
  
  //print $newItem->getSelect();
  if($newItem->count() == 0){
      $newItem = Mage::getModel('eav/entity_attribute');
      $newItem->setEntityTypeId($attSet->getId()) // catalog_product eav_entity_type id ( usually 10 )
         ->setAttributeSetId($setId) // Attribute Set ID
         ->setAttributeGroupId($groupId) // Attribute Group ID ( usually general or whatever based on the query i automate to get the first attribute group in each attribute set )
         ->setAttributeId($attId) // Attribute ID that need to be added manually
         ->setSortOrder(10) // Sort Order for the attribute in the tab form edit
         ->save()
      ;
  }
  
  echo "Attribute ".$attCode." Added to Attribute Set ".$set->getAttributeSetName()." in Attribute Group ".$group->getAttributeGroupName()."<br>\n";
}

?>