Yes, JMeter can record HTTP or Https request going to the server from your mobile application also. It is required that mobile and JMeter are on the same network.
Below is the configuration required:
Configure your proxy server in JMeter to run at a specified port.
Set up the proxy on your mobile wifi settings and enter the same port number that is used in ...
JMeter automatically treats HTTP status codes below 400 as successful so if your application responds with "invalid credentials" message but having status code of 200 - JMeter will mark the request as "passed".
If you want JMeter to conditionally consider request as failed if i.e. "Welcome" text is missing or login form is still ...
So, there are three main components of mobile app performance:
When it comes to the backend, the things related to performance that are important to know when an app is under load are the server response times, database queries times, and the server’s resource usage.
This is where load testing with a tool like BlazeMeter ...
It depends how complex the transformations are, if you can query both the input and the target tables than maybe a simple record count, a column sum and checking first, last and a row in the middle could be sufficient to tackle most risks.
Checking Data Completeness is done to verify that the data in the
target system is as per expectation after loading.
Given you're talking about "millions" it makes sense to use a load testing tool which can do multiple actions in parallel. If you don't have a better candidate yet you can consider Apache JMeter which provides:
CSV Data Set Config - so you can read "expected" data from file(s) in your local file system
JDBC Request sampler - to execute ...