I'm currently planning a script which will update an additional field on our subscribers from an external database with around 200,000 entries but need to cross-check each.
Is there any limit on the no. requests we can push to the API during a period of time etc which is likely to pose a problem here?
The only limit in that sense is the one which will be imposed by network performance. 200,000 individual checks and updates will take a very long time. You can reduce that considerably by batching your subscribers. Rather than cross-checking them and then updating them each individually, you could consider getting a batch of 1000 active subscribers, cross check them all, and then update that whole batch in one call.
Apologies if i haven't correctly understood your use case, but if i have then going that will reduce the total number of calls and dramatically increase the speed of your update script.
From Australia to Zimbabwe, and everywhere in between, companies count on Campaign Monitor for email campaigns that drive real business results.Get started for free