One of our customers has a website powered by a legacy Django web application. While the web application is built with old technologies (Python 2.7, Django 1.7) that have been obsoleted, it is stable and gets rarely updated.

One of our customers was recently confronted with a SQL migration problem of their PostgreSQL database.

In database applications, it can happen that some information get stored as an encoded comma separated string. After some time, it is recognized as an error in the modeling and this information must be split into individual values and inserted into a child table. The problem is to find an efficient way to insert these values into the child table.