Overview of Data Model components
The data model consists of several structural elements used to design application data structures:
- Tables: Contain columns and rows (records). They are the primary physical storage units.
- Views: Provide a runtime presentation of data from one or more tables. Views are always up-to-date and do not store rows themselves.
- Snapshots (DB2/Oracle): Similar to views but physically save the combined data from one or more tables to improve performance. These can be refreshed manually or automatically by the RDBMS.
- References: Relations between a source table (lookup table) and a target table. Integrity is automatically guaranteed via column comparison.
- Function-typed tables: Read-only tables that use a table-valued function as a data source to improve performance by filtering data via parameters before retrieval.