App Insights has some pre-defined tables that you insert data into. Those tables have specific schema related to monitoring apps/web apps. It is possible to use the HTTP Data collector API but then you will have a custom table where the data will be sent. When you use the HTTP Data collector API keep in mind that the data will not be visible into the App Insights experience. You can still use some of the common features like alerts. If you have app I would suggest using the App insights integration to monitor rather than using HTTP Data Collector API. The latter is more useful if you have some logs that do not fit into the App insights model or you do not want to use App insights at all for your app monitoring. Keep in mind that there is a new API for sending custom logs. That API will replace the HTTP Data Collector API in the future. Currently no deprecation dates are announced. Usually when deprecation is announced you have 1 to 3 years to migrate from the time of announcement.
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