Table Data Gateway and Row Data Gateway are two design patterns that are very closely related. The former specifies an object that acts as a gateway from our system to a table in a database. This means that it will give us the functionality necessary to execute all common operation to that table easily by providing methods to all the CRUD (Create, Read, Update, Delete) operations.
Row Data Gateway provides very similar functionality, but it lets you execute those operations in a single record of a table.
The Zend implementation
Zend Framework provides us with Zend_Db_Table as an implementation of the Table Data Gateway pattern and Zend_Db_Table_Row as an implementation of the Row Data Gateway pattern. The best way to use these implementations is by extending Zend_Db_Table_Abstract and Zend_Db_Table_Row_Abstract respectively.