Model 204

Model 204 is a legacy database system developed by Computer Corporation of America, one of the oldest database systems still in limited use.

Why Agent Required

Model 204 runs on mainframe systems that cannot directly upload data to the web. The DataMeans Agent connects securely to your environment for extraction.

What You Can Extract

• Model 204 versions 2.x through 4.x
• Model 204 database files (internal Tables A through D)
• Table and record structures
• B-tree indexes

What You Get Out

DataMeans converts your data into multiple modern formats:

Output	Description
csv/{TableName}.csv	One CSV file per table with all row data
xlsx/{TableName}.xlsx	Excel workbook per table (omitted for tables over 1,048,575 rows, 16,384 columns or 8,000,000 cells - see note below)
xls/{TableName}.xls	Legacy Excel format per table (omitted for tables over 65,535 rows, 256 columns or 150,000 cells - see note below)
json/{TableName}.json	JSON array of records per table
json/{TableName}.jsonl	Newline-delimited JSON (streaming-friendly)
postgres.sql	PostgreSQL CREATE TABLE + INSERT statements
mysql.sql	The same schema and rows, in MySQL dialect
sqlite.sql	The same schema and rows, in SQLite dialect
ansi.sql	The same schema and rows, in portable ANSI SQL
sqlserver.sql	The same schema and rows, in SQL Server (T-SQL) dialect
report.json	Structured conversion report
report.md	Human-readable conversion summary

How It Works

Agent availability: The DataMeans Agent is currently in development and not yet available for download. The steps below describe the planned workflow. To get notified when Model 204 support launches, reach out via our About page.

1. Download and install the DataMeans Agent on a system with Model 204 access
2. Configure connection to your database environment
3. Select schemas and tables to extract
4. The Agent extracts data and uploads securely to DataMeans
5. Review and download your converted data

Planned Support

• Record structure extraction
• Index analysis
• Variable-length record handling
• B-tree recovery

Known Limitations

• Requires DataMeans Agent installation
• Very specialized format may require consultation
• Limited documentation available

Note on the Excel formats. An .xlsx sheet holds at most 1,048,575 rows of data and 16,384 columns, and a legacy .xls sheet 65,535 rows and 256 columns. Rather than ship a file that looks complete but is silently cut short, DataMeans leaves a table out of any Excel format it does not fit and notes it in the job report. The .xlsx copy is also left out for tables of more than 8,000,000 cells (1,048,575 rows of 12 columns is 12.6 million), which take too long and too much memory to write, and the .xls copy for tables of more than 150,000 cells, which the legacy format takes far too long to write. The CSV, JSON and SQL outputs always contain every row.

Overview

Documentation coming soon.

This article will contain vendor-neutral technical documentation about the Model 204 database format, including:

• History and background
• File format specifications
• Data types and structures
• Version differences
• Technical references