val keyColumnsDefinitionDB: List<Pair<String, String>> (source)
It is the list of all the column names and their definition that identify a key.
This method provides the column scheme for the key type (K) managed by the current KeyParser object. This method will be used by the Connector class at the moment of defining the table persisting the DB-tree.
keyColumnsDefinitionDB - the list of pairs: <columnName, columnDefinition>. ColumnDefinition must
be understood and interpreted by the underlying database to define the the corresponding column.