Both Oracle and PostgreSQL are known as extremely popular object-relational database management system sen riched by powerful features and tools. However, PostgreSQL is open source and consequently it has much less total cost of ownership and more liberal license than Oracle. This is the main reason why a lot of organizations migrate their Oracle databases to PostgreSQL.
The process of Oracle to PostgreSQL database migration usually goes according to extract-transfer-load (ETL) technique consisting of the following steps:
- Export Oracle schemas, indexes and constraints in form of CREATE-statements of data definition language (DDL)
- Convert those statements in PostgreSQL format with respect correct type mapping and replace all Oracle built-in functions missing in the target DBMS that may be used as default values for table columns
- Import the resulting statements into PostgreSQL database
- Extract data from Oracle database in comma-separated values (CSV) format
- Take care about PostgreSQL format of dates, binary data and escape special symbols in text fields
- Load the converted CSV files into the PostgreSQL database
- Export Oracle stored procedures, views, and triggers as SQL statement and source code, convert it according to PostgreSQL dialect of PL/SQL and import to the target database
From the steps above it is clear that manual migration from Oracle to PostgreSQL is not an easy task. There is high risk of data loss and corruption or some other errors due to the human factor. In order to avoid this risk and to simplify database migration process special software must be used.
Converters from Oracle to PostgreSQL are provided by few software companies specializing on solutions for automating database migration.One of such tools to automate Oracle to PostgreSQL database migration within a few mouse clicks has been developed by Intelligent Converters software company.
Product Features:
- Table definitions, constraints, data, indexes and foreign keys are converted as database objects.
- To reach a high performance of the database conversion process, the converter implements direct connection and bulk insert technique.
- All versions of Oracle and PostgreSQL are supported including the variation of these database management systems and “software as a service” (SAAS).
- Oracle to PostgreSQL converter provides command and line support for the purpose of automation.
- Existing PostgreSQL database with Oracle base is done by the converter which allows to merge and synchronize.
- Settings of conversion are stored in the profile.
One of the most powerful product features is converting data filtered by SELECT-queries. This feature allows to select particular columns and data subset, merge data from multiple tables into a single one or just rename some columns in the resulting table.
As every product of Intelligent Converters, Oracle to PostgreSQL converter is supplied with free demo version that is limited to 50 rows per table and does not convert foreign keys.