How to create alerting on delta pattern capture in Log File Extension Monitoring

[Udit.Jain]

We are monitoring a log file, which gets refreshed on daily basis. The first occurrence of a specific pattern can be easily captured & alerted with the value. But upon every other poll same occurrence is again captured & the metric value shows as 1. How to create alerts when the subsequent occurrence is captured i.e. 2,3, and so on.

Also, keeping in mind that as the day changes, this should also get refreshed & start capturing from 0 next day onwards.

Any suggestions??