I saw a LinkedIn post by Ravikiran Tirumala, Commissioner of Electronic Services Delivery at the Government of Telangana, India, that stopped me in my tracks. He announced that MeeSeva, Telangana's largest citizen services platform serving nearly 200 Million citizens, had completed its Oracle to PostgreSQL migration using Ora2Pg, the open-source database migration tool I started developing over two decades ago. 80,000 government-to-citizen transactions a day. 15 years on Oracle. Migrated to PostgreSQL in under 4 hours of downtime. Citizens barely noticed.
The savings? Oracle licensing and maintenance was costing approximately ~$1.2M USD. The entire migration cost mentioned by Ravikiran was under USD 120,000. That means the migration paid for itself in the first month, and every dollar saved after that goes straight back to the people of Telangana. Permanently.
I will be honest, when I read Ravikiran's words acknowledging Ora2Pg and the PostgreSQL community by name, I was genuinely touched. When I started building Ora2Pg in 2001, I never imagined it would one day help a state government in India save its taxpayers this kind of money. That is the power of open source, you build something, you give it freely, and years later it shows up in places and at scales you never anticipated.
To Ravikiran and the MeeSeva team - thank you. This recognition means to me and my team at HexaCluster, more than you know.
Ravikiran said something in his post that deserves repeating -
"Every state government. Every central ministry. Quietly renewing Oracle licenses year after year — not because PostgreSQL wasn't ready, but because nobody wanted to go first."
Telangana state went first. And they proved it works - at scale, in production, serving real citizens. This is not a proof of concept. This is not a sandbox experiment. This is a mission-critical government platform handling 80,000 daily transactions running on PostgreSQL, migrated with open-source tools.
Every government organization, every enterprise paying millions in Oracle licensing fees should be asking themselves the same question Ravikiran posed - how much longer will you keep paying to avoid open source?
For those unfamiliar, Ora2Pg is the world's most widely-used open-source Oracle to PostgreSQL migration tool. I started developing it in 2001 and have been maintaining it, with contributions from the community and from my team at HexaCluster, for over 24 years.
I am Gilles Darold, CTO of HexaCluster, an expert in Database and Application Migrations.
Here is what Ora2Pg does
Ora2Pg has been adopted by some of the largest technology organizations in the world as their foundation for Oracle to PostgreSQL migration -
When your tool is the one that Google, Microsoft, and Yugabyte chose to build on - that is not an accident. That is 25 years of understanding what Oracle-to-PostgreSQL migration actually requires at the schema, data, and procedural code level.
HexaCluster Corp. is the company I co-founded with Avinash Vallarapu.
HexaCluster is not a company that stumbled into database migration. We are the people who built the tools the industry relies on. Under my leadership, our team has authored/contributed to 50+ PostgreSQL tools and extensions and has been solving migration problems w.r.t Oracle, SQL Server, MySQL, MariaDB, DB2, Sybase.
That depth of experience is exactly why we built HexaRocket.
The MeeSeva migration is a tremendous success story. But let us examine one number honestly: 4 hours of downtime.
For MeeSeva, 4 hours was acceptable and well-managed. But consider what 4 hours means for systems that cannot afford even minutes of interruption -
For these systems, 4 hours is not an option. Even 30 minutes is not an option.
This is exactly the problem HexaRocket was built to solve.
HexaRocket is our enterprise database migration tool, born from everything we learned building and maintaining Ora2Pg for 25 years. It takes what Ora2Pg does well and adds the capabilities that mission-critical, zero-tolerance-for-downtime environments demand -
HexaRocket includes a built-in CDC (Change Data Capture) engine. While the bulk of your data migrates, CDC continuously captures every INSERT, UPDATE, and DELETE happening on your source Oracle database and replicates it to PostgreSQL in real time. When you are ready to cut over, the gap is seconds but not hours.
For a platform like MeeSeva, this could mean migrating while citizens continue using the system, with a cutover window measured in seconds rather than hours.
One of the biggest fears in any Oracle to PostgreSQL migration is: what if something goes wrong after cutover? With Ora2Pg, rolling back means restoring from backup, which adds hours of risk.
HexaRocket provides reverse replication after cutover, changes on the new PostgreSQL database are replicated back to Oracle in real time. If anything unexpected happens, you switch back instantly. This safety net changes the risk calculus of migration entirely.
Ora2Pg does a remarkable job converting Oracle schemas to PostgreSQL up to a good extent, and I built it to handle the real-world complexity that tools built by people who have never run a production Oracle database simply miss. HexaRocket takes this further with an AST-based conversion engine and 5 layers of validation that verify every converted object against syntax, semantics, and runtime behavior.
For complex PL/SQL that cannot be deterministically mapped, HexaRocket uses AI within a constrained, validated pipeline, not as a black box, but as an accelerator whose output is verified before it reaches your database.
This help you migrate faster and seamlessly within lesser budget than you could imagine.
Ora2Pg is a command-line tool, powerful, but it requires expertise. HexaRocket provides a rich web-based interface with centralized visibility, real-time progress tracking, guided workflows, Schema Validation, Data Migration and CDC with Validation. This means your team gets a clear picture of where the migration stands at every moment, without parsing log files.
While Ora2Pg focuses on Oracle and MySQL to PostgreSQL, HexaRocket supports migrations from Oracle, SQL Server, MySQL, MariaDB, PostgreSQL, Sybase to targets including PostgreSQL, and Yugabyte, MariaDB, SQL Server, Google BigQuery, AlloyDB, Cloud SQL, AWS RDS, and AWS Aurora.
There is another hidden cost in every Oracle to PostgreSQL migration that rarely makes the headlines: application code that still speaks Oracle.
Even after the database is migrated, applications are often riddled with Oracle-specific function calls like NVL, DECODE, TO_CHAR with Oracle formatting, DBMS_OUTPUT, UTL_FILE, DBMS_LOB, and dozens of PL/SQL package references. Rewriting all of that application code is expensive, error-prone, and time-consuming. In many migrations, the application layer rewrite takes longer than the database migration itself.
This is exactly what HexaBridge from HexaCluster solves.
HexaBridge is our Oracle compatibility layer for Community PostgreSQL, not a proprietary fork, but a set of extensions that bring Oracle's types, functions, and packages directly into standard PostgreSQL. The numbers speak for themselves:
DBMS_OUTPUT, DBMS_LOB, UTL_FILE, DBMS_SQL, DBMS_SCHEDULER, and many more)VARCHAR2, NUMBER, DATE with Oracle semantics, RAW, XMLTYPE)What does this mean in practice? A platform like MeeSeva, with 15 years of Oracle-native application code, could migrate and have its application layer continue working with minimal changes. Oracle function calls that would normally require rewriting simply work on PostgreSQL with HexaBridge installed.
This dramatically compresses the migration timeline. Instead of spending months rewriting application code after the database move, teams can migrate the database, install HexaBridge, and have the application running, then refactor Oracle-specific calls to native PostgreSQL at their own pace, without blocking the migration.
Combined with HexaRocket's near-zero-downtime CDC and Ora2Pg's proven schema conversion, HexaBridge completes the picture: migrate the database with confidence, keep the application running without rewrites, and modernize incrementally.
The MeeSeva story is a signal. Telangana government has demonstrated that Oracle to PostgreSQL migration is not just technically feasible at government scale, it is financially irresponsible not to do it.
If every Indian state government followed Telangana's lead, the aggregate savings in Oracle licensing alone would run into hundreds of crores per year money that could fund schools, hospitals, and infrastructure instead of database license renewals.
And it is not just government. Every enterprise paying Oracle licensing fees for workloads that PostgreSQL can handle should be running the numbers.
The tools exist. Ora2Pg is free, open source, and proven at scale. For organizations that need zero-downtime migration, real-time replication, built-in rollback, and enterprise support, HexaRocket is ready.
We built both. We maintain both. And stories like MeeSeva remind us why this work matters.
If you need expert support migrating legacy or complex Oracle, SQL Server, MySQL, or MariaDB databases to PostgreSQL or distributed databases, we’re here to help.
HexaCluster provides end-to-end migration and modernization services, including application migration and modernization, database migration, and PostgreSQL consulting such as performance tuning, health audits, managed DBA services, and 24/7/365 support.
To start a conversation or explore how we can support your migration journey, please contact us at connect@hexacluster.ai
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Gilles Darold is the CTO of HexaCluster. Gilles is one of the Major PostgreSQL Contributors and the creator of Ora2Pg, pgBadger, and many more popular PostgreSQL tools and extensions. His leadership has enabled HexaCluster in contributing to 50 plus popular PostgreSQL extensions and also create multiple PostgreSQL tools and extensions. Gilles is an expert in all the popular programming languages and is always passionate about contributing to PostgreSQL.
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