Скачать или смотреть How to Resolve the plpython2 Extension Error When Upgrading from PostgreSQL 9.6 to 13

Upgrade PostgreSQL smoothly by fixing plpython2 extension issues. Follow our guide to identify and remove dependent functions easily.
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Navigating the plpython2 Extension Upgrade Challenge in PostgreSQL

Upgrading PostgreSQL can often seem straightforward, yet it can present unexpected challenges. One common issue arises when transitioning from PostgreSQL 9.6 to PostgreSQL 13—specifically, an error related to the plpython2 extension. If you’ve found yourself grappling with this problem, you're not alone. Let’s explore the situation and discover a clear path to resolution.

Understanding the Problem

When attempting to upgrade, you may encounter an error message indicating that certain loadable libraries, like plpython2, are missing from the new installation. The error might look something like this:

[[See Video to Reveal this Text or Code Snippet]]

The underlying issue is straightforward: your database (in this case, infohub) previously utilized the plpython2 extension, which is not compatible with PostgreSQL 13. However, removing the extension does not automatically resolve the problem, as you may still have dependent functions lingering in your database.

Steps to Solve the Issue

Here’s how you can address the plpython2 extension error efficiently and ensure a successful upgrade to PostgreSQL 13.

1. Identify Functions Dependent on plpython2

First, you need to check for any functions that might still depend on plpython2. Run the following SQL command in all databases to identify them:

[[See Video to Reveal this Text or Code Snippet]]

2. Review the Results

Once you execute the query, you’ll receive a list of functions that depend on the plpython2 library. This step is crucial because it helps you pinpoint exact dependencies preventing the upgrade. If the command returns no results, ensuring no remnants of plpython2 exists becomes a bit tougher, as we initially believed no dependencies were present.

3. Remove Dependent Functions

If the previous command identifies any function names, you can then remove them using the DROP FUNCTION SQL command. Be cautious and ensure you’re removing only functions that are no longer needed or that you can rewrite in another language.

4. Verify Extensions and Dependencies

After removing the necessary functions, double-check to ensure that the plpython2 extension has been appropriately removed with:

[[See Video to Reveal this Text or Code Snippet]]

5. Run pg_upgrade Again

Finally, after cleaning up your database of any dependent functions on plpython2, you should attempt to run the pg_upgrade process again. If everything has been cleared correctly, your upgrade to PostgreSQL 13 should proceed without any further issues.

Conclusion

Encountering the plpython2 extension problem during a PostgreSQL upgrade can be frustrating, but it’s also a manageable hurdle. By following the steps outlined above, you can effectively identify and eliminate dependencies linked to that extension, setting the stage for a successful upgrade to PostgreSQL 13.

If further issues arise, remember that community forums and documentation are excellent resources to seek guidance. Happy upgrading!