VX/DATAX - OpenVMS RMS Data exchange

Overview

VX/DataX is a powerful data migration and conversion tool that allows users to:

• Transport OpenVMS RMS data files to Linux

• Convert and transform data schemas for compatibility with target platforms

• Support multiple data formats, including SEQUENTIAL, RELATIVE, KEYED SEQUENTIAL, and VIRTUAL BLOCK FILES

• Recreate files in the original format while ensuring data integrity

• Perform automatic endian and floating-point conversions (DEC to IEEE, Little Endian to Big Endian, Quadword Date/Time to Linux/Windows format)

VX/DataX integrates seamlessly with VX/RMS, ensuring that data can be used directly by applications running on modern platforms.

VX/DataX Features

Feature	Description
Full RMS File Support	Supports SEQUENTIAL, RELATIVE, KEYED SEQUENTIAL, and VIRTUAL BLOCK FILES.
Data Format Conversion	Automatically converts DEC FLOAT to Intel IEEE and Little Endian to Big Endian.
Portable Data Containers	Packs VMS data files into a portable container for easy transfer.
C-ISAM Format	Recreates RMS files using industry- standard C-ISAM format.
RMS Key Preservation	All ISAM keys are fully recreated for relational consistency.
Floating Point Handling	Ensures compatibility with IEEE 488 floating-point standards.

VX/DataX Workflow

VX/DataX ensures a seamless data migration process, maintaining data structure and precision while converting formats.

1️⃣ Pack VMS RMS Data into Portable Format

VX/DataX extracts data from OpenVMS RMS files and encapsulates them in a portable container file.

VX/DataX extracts RMS files and packs them into a cross-platform format.

2️⃣ Convert Data Types for Target Platform

VX/DataX allows customizable data transformations, ensuring compatibility with modern architectures.
‍

VMS Data Type	Converted Linux/Windows Format
DEC Floating Point	IEEE 754 Floating Point
Little Endian Integer	Big Endian Integer (if required)
Quadword Date/Time	Standard Linux/Windows DateTime

3️⃣ Recreate RMS Data in VX/RMS on Linux & Windows

The packed data is unpacked and recreated in the exact format, ready to be used by VX/RMS.

Before Conversion (VMS RMS)

RMS Indexed File: EMPLOYEE.DAT
Key: Employee_ID
Record: 256 bytes
Floating Point: DEC Format

After Conversion (VX/RMS on Linux)

C-ISAM Indexed File: EMPLOYEE.DAT
Key: Employee_ID
Record: 256 bytes
Floating Point: IEEE 754 Format

Precision & Accuracy Considerations

Integer Data (Short & Long)

✅ Converted perfectly with no loss of accuracy.
‍

Floating-Point Data (DEC → IEEE 488)
‍

⚠️ Potential loss of accuracy due to precision differences.

• DEC Floating Point provides 4 more digits of precision than IEEE 488.

• IEEE 488 has a larger numerical range, but slightly reduced accuracy.

VX/DataX applies intelligent rounding techniques to minimize accuracy loss.

Why Use VX/DataX?

✅ Accurate & Efficient Data Migration

✅ Preserves RMS File Structure & Keys

✅ Converts Data Types for Cross-Platform Compatibility

✅ Seamless Integration with VX/RMS on Linux & Windows

VX/DataX ensures that legacy VMS RMS data remains accessible and usable, enabling a smooth transition to modern platforms while maintaining data integrity.