Chrysalis provides all the benefits of a relational database to a legacy application with low risk and minimal disruptions to business operations.
Chrysalis allows legacy COBOL programs to benefit from the relational database by
providing ways to easily integrate relational
database operations into legacy code without
impacting the existing business logic.
Performance Improvements via Load/Fetch
Chrysalis provides the means for COBOL to
take advantage of a relational database's
inherent performance abilities across large
datasets.
This is achieved through making two new
COBOL I/O functions available – LOAD and
FETCH which are used in place of the
commonly used START / READ NEXT loops
where a file is read, one record at a time, over a large range of records.
The LOAD function allows for the specification
of START and END key values, and replaces
the START in a START / READ NEXT loop.
|
It creates an in-memory dataset of all the
records to be read. The FETCH replaces the
READ NEXT (or PREVIOUS) statement.
This results in one “real” IO statement at the
start of the loop instead of one for each record
read, providing significant performance
improvements even compared to native
COBOL files.
Performance Tailoring via Customized
Load/Fetch
Customized LOAD/FETCH statements allow
commonly used search criteria, such as the
customer records for a particular branch
operation, to be placed in a “Customized
Load”.
This has proven to be an extremely powerful
function which not only yields significant
performance improvements but also forms the
basis of a set of library routines which result in
simplified, safer COBOL code. |
Performance Improvement & Code Simplification via Virtual Files
An extension of customized LOAD/FETCH ,
VIRTUAL FILES allows commonly used record
sets comprised of data from multiple files to be
treated by COBOL as one file.
|
