When you create a attribute for a product EAV comes in a picture. To get a value you need to know basics, which magento uses to store eav data.
For this following tables plays a important role.
eav_attribute
Whenever you create a attribute this table gets entry which stores all important data which helps to make a relation, like entity_type_id,attribute_code,backend_type and many more but this are the important fields.
eav_entity_type
Magento has 8 types of entity, by which, type of attribute is decided. in your case it is catalog_product
- customer
- customer_address
- catalog_category
- catalog_product
- order
- invoice
- creditmemo
- shipment
- How we say it is catalog_product in your case ?
- So the answer is as i said above when you create a new attribute their will be a entry in eav_attribute and if you check this entry their will be a column as entity_type_id whose value is 4 which is nothing but a catalog_product of eav_entity_type table.
eav_attribute table also has a column known as attribute_code which is nothing but a value of Attribute Code entered while making a new attribute from admin.
So as in your case we find it as a catalog_product we will look for all tables whose initial are from catalog_product you will get a table whose ending is like datetime,decimal,text,varchar,text,int etc.
catalog_product_entity is the primary table for product, our product id is nothing but a value of entity_id of this table.
How we get a desired table ?
in eav_attribute table their is a column backend_type by which we decide on which table we get a values. In your case it might be varchar. So we are going to look for a catalog_product_entity_varchar table. in this table we will search for a attribute_id and entity_id which is a product id and which we can see in admin grid and which is equal to entity_id of catalog_product_entity table.
Its time for a practical !!!
suppose your product id is 13
your attribute code is catalog_special_name
So in eav_attribute table we will search for a record whose attribute_code = catalog_special_name and we will get a useful information which is attribute_id,entity_type_id and backend_type.
lets say attribute_id = 138,entity_type_id = 4 and backend_type = varchar.
so as we got entity_type_id = 4 we will look in eav_entity_type table and confirm that our attribute is for catalog_product.
Then its time for catalog_product_entity_varchar table here we will search a record for whose attribute_id = 138 and entity_id = 13 which is our product id and that’s it here you get a value.