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The template macro then generates the emulation source code, with the dummy
variable being replaced by the saved tokens selected earlier.
A sample macro is shown below:
UPDATE PERFORM !TAB-NAME^-REPLACE-!SERIALNO^
!FULLSTOP^
UPDTWH !TAB-NAME^-REPLACE-!SERIALNO^.
EXEC DLI GHU USING PCB(1)
SEGMENT (!TAB-NAME^)
INTO (!TAB-NAME^-AREA)
SEGLENGTH (!TAB-NAME^-LEN)
WHERE (!WHERE-CL^)
FIELDLENGTH(!FLD-NAME^-LEN)
END-EXEC.
IF DIBSTAT = 'E'
MOVE +100 TO DLICODE
ELSE
COMPUTE !SET-CLUA^
EXEC DLI REPLACE
END-EXEC.
5.9 Reengineering Relational Database Programs into
Object-Oriented Database Methods
Our methodologies can reengineer traditional record-based database systems into
table-based database systems, and to integrate a database system with an expert
system into an object-oriented system. As object-oriented paradigm is the trend of
computer technologies for better productivity, we must reengineer existing database
systems into object-oriented databases too. We have described the schema transla-
tion and data conversion from a relational database to an object-oriented database.
This section is to describe how to translate relational database programs (i.e., em-
bedded-SQL programs) into object-oriented database programs.
Relational database programs can be defined as program logic with nonproc-
edural call of embedded-SQL statements. In general, object-oriented database pro-
grams are encapsulated methods in each object. The participated boundary of rela-
tional database programs are more general. However, the participated boundary of
object-oriented database methods is bounded by each object. As a result, the func-
tional specification of relational database programs are multi-threaded with many
outputs (i.e., many inputs and many outputs), while the functional specification of
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