Filter
Top Products
Coexistence General information
38 U929-J-Z125-9-76
In summary, UDS/SQL offers the following options for combining program interfaces and
data organizations:
Figure 5: Coexistence of interfaces and data models in UDS/SQL
Relational SQL program interface → CODASYL data organization (RC)
Via the relational SQL program interface, applications access a CODASYL data organi-
zation for which a relational view has been generated as described above. This combination
of program interface and data organization will be referred to in the following as an RC
combination.
An RC combination makes it possible to take advantage of the implicit set relations without
requiring SQL programmers to be acquainted with the CODASYL structures. By taking
advantage of these set relationships, UDS/SQL ensures the integrity of the data relation-
ships (referential integrity).
CODASYL
application
SQL
application
UDS/SQL
CC RR
RC
CODASYL data structure
Relational data structure
CODASYL-
DML
interface
Relational
SQL-DML
interface