Magento Maximum Length of Attribute

In Magento By default maximum length of an attribute is less than 30 synbols

we can upgrade to new value just need to edit one file

app/code/core/Mage/Eav/Model/Entity/Attribute.php copy to

app/code/local/Mage/Eav/Model/Entity/Attribute.php and

Find  CONST ATTRIBUTE_CODE_MAX_LENGTH = 30; and

Replace CONST ATTRIBUTE_CODE_MAX_LENGTH = 50;

Hope this will help you