This class can be used to wrap the access to individual MySQL database table rows in class objects.
Each object of the class stores the values of the fields of a given row of a given table.
The class provides means to store and retrieve the values of the row fields in the specified table.
It can retrieve the row values given the value of a field named 'id' or named 'name'. The field values are stored in class variable that is an associative array.
Then the class can also store the eventually modified table fields values. If the id field value is set to 0, the class inserts a new table record.