How to Transition Easily to PostgreSQL from Oracle

If you need to transition easily from Oracle to PostgreSQL without worrying about type conversions or other Oracle packages that require modifications to be PostgreSQL-compatible, a useful solution is IvorySQL!

Introduction

More and more companies are seeking to free themselves from the costs and constraints of Oracle by migrating to PostgreSQL. But how can this transition be achieved without spending months on it? Here is a proven, fast and secure method, based on feedback and open source tools.

Start by assessing and mapping

Before migrating, it is essential to take stock of the situation: we start by listing Oracle objects through performing a complete extraction (including tables, views, sequences, procedures, functions, and packages).

It is also important to communicate regularly with the client to refine findings and validate directions, as well as to identify dependencies (applications connected with which technology, jobs, interfaces, etc.).

Finally, identify the client’s Oracle-specific features (specific functions such as ROWID, DUAL, DBMS_XXX, etc.) and any other keywords requiring special attention.

Choosing the right open source tools

The success of a transition to PostgreSQL – because it is indeed a gradual transition and not a migration – depends as much on strategy as it does on tools.

It is not enough to simply copy objects: you need to understand the subtleties of the Oracle engine and intelligently transpose them into the PostgreSQL universe.

Among the essential tools, Ora2Pg plays a central role. Not only does it generate clear inventory reports, it also automates the conversion of schemas, data and PL/SQL code. It is a valuable accelerator for well-structured projects.

But in some contexts, the reality is more complex. Many customers accumulate significant technical debt, with thousands of lines of procedural code. Attempting to rewrite everything in PL/pgSQL in a short period of time would exhaust teams and compromise the migration itself. Maintaining two code bases— one in PL/SQL, the other in PL/pgSQL— during a complete transition phase is often organisationally untenable.

This is precisely where IvorySQL offers a powerful alternative. This fork of PostgreSQL, enhanced with Oracle compatibilities (PL/SQL, ROWID, DUAL, etc.), significantly reduces the need for immediate rewriting. By combining IvorySQL with targeted documentation and business validation scripts, the transition is easier, more reliable, and above all, more controlled.

Once in production, teams have the time they need to gradually rewrite their procedural and remaining application code in PL/pgSQL, without pressure or functional disruption.

Integration and tests

One of the great advantages of IvorySQL is that it performs part of the integration upstream. Thanks to its native support for PL/SQL, Oracle objects and Oracle-compatible syntax, many elements migrated via Ora2Pg work immediately without any major adaptation.

Of course, this does not eliminate the need for testing. On the contrary, it is essential to validate business behaviour in an IvorySQL pre-production environment. Procedures, functions, packages, triggers, and views must be tested with real-world cases, comparing the results between Oracle and IvorySQL to ensure functional equivalence.

Comparison scripts can be used to verify query responses, transaction effects, or the behaviour of migrated functions. But in many cases, IvorySQL significantly reduces the need for patches or rewrites, speeding up production and securing the transition.

Document and support

A successful transition is not limited to technical aspects; it also relies on clear documentation and appropriate support. It is essential to write comprehensive test specifications for each complex object and module (procedure, package, trigger, etc.) in order to keep track of technical choices, adaptations made, and points of attention.

Support for client teams is just as important. Targeted workshops are used to share best practices, explain the differences between Oracle and PostgreSQL, and facilitate the adoption of IvorySQL.

Finally, a successful transition to PostgreSQL also depends on support for technical and functional teams. Targeted training sessions enable developers, DBAs, and project managers to learn the specifics of IvorySQL, understand the differences with Oracle, and quickly develop their skills.

This system also relies on structured technical support, which helps resolve issues, secure implementation choices, and facilitate communication between project teams and migration experts.

IvorySQL in the real world

During a recent assignment for a private sector company, we supported the transition from an Oracle database to IvorySQL in a challenging context: where there was significant technical debt, high volume, and tight deadlines.

Thanks to IvorySQL and our ability to automate this transition, it was completed quickly and almost all objects were integrated without rewriting.

The switch from IvorySQL to PostgreSQL can be carried out smoothly, as long as the application is fully functional and meets business expectations.

The teams were able to focus on business testing, while targeted training and technical support enabled rapid skill development.

It is essential to succeed in this type of project in order to build confidence and roll out this operation across your entire Oracle instance fleet!

Are you considering a transition from Oracle to PostgreSQL? Let’s talk about it.

Contact our team of experts at any time: contact@data-bene.io

On November 26, 2025 IvorySQL 5.0 was released - view the announcement here for more information about this open-source project.