A table is the most commonly used block datasource. Unless you have special needs, a table is the best choice for a block datasource.
A data block that is based on a table allows the end-user to:
A data block based on a table, also reduces network traffic through array processing.
The Query Array Size property enables array processing for records queried, and the DML Array Size property enables array processing for records used in DML operations.
Query Data Source Type property
Guidelines for choosing block datasources
Using transactional triggers as block datasources
Using stored procedures as block datasources