Recently I have been working on a data warehouse project that is trying to extract billing and payment information from a range of cloud services. In all cases it seems that the data needed by the accountants has not been given the care that it needs.
The industry practice seems to be log into a portal and download a spreadsheet of data that may be accurate or timely. Any api’s exposing this data seem to only work on a per order basis – which means that an attempt to keep a database upto date could require geometrically increasing processing times (you need to check each order for changes to a transaction). These api’s tend to be heavily restricted on the volume of data per call (hundreds of transactions per call) combine this with a frequently undocumented rate limit make catching up historical data difficult at best.
If you are providing services that accountants need think about providing an api that makes reconciliation easy. Reconciliation is important especially if you want to get your tax calculations right.
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