I know some basics on callouts but would like some advice on doing multiple callouts.
Requirements: I have an external system where guests are registered this could be large amounts. I have to get these into Salesforce and also check if there are updates to these external records. This has to be near realtime.
How does for example handeling 1 million records work. Does the callout make partitions and batch process these records?
If a record changes in the external system do I need to do a callout for all the records and check for changes?
If I do a callout every minute do I run into limits and will my object be locked all the time?