The following...

We,ve got clients working with us in contracts. Per client several contracts of a certain type with start- and end dates.

If I need aggregated info per client in one record like:

• how many different contract did the client have
• of which type
• when was the dateof the first contract
• and the last contract
• how long have we been working with him.

The information from the sourcedatabase is uploaded in our DWH in Parquet files.

Should/can I use Python on Parquet to aggregrate this data? Looping over the source tables and create a table with the aggregated data?