The Object | Relational Gap |
transient | persistent |
classes | tables |
| |
attributes | columns |
objects | rows |
- instance attribute
- implicity ID: reference
|
- field
- explicit ID: primary key
|
relations | relations |
- references
- unidirectional
- ordered (lists)
|
- foreign keys
- bidirectional
|
behaviour centric | data centric |
- navigate to object
- behaviour based partitioning
- methods
|
- operate on set
- relation based partitioning
- stored procedures
|
- tight behaviour-data coupling
|
|
- data hiding, encapsulation
|
|
|
|
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