filter alarm table

[admin]

Date/time is stored as UNIX timestamp. Check for month number wrap is not needed, it is handled by the os.time() automatically.

Code:

date = os.date('*t')
date.day, date.hour, date.min, date.sec = 1, 0, 0, 0
ts_end = os.time(date)
date.month = date.month - 1
ts_start = os.time(date)
alerts_table = db:getall('SELECT * FROM alerts where alerttime BETWEEN ? AND ? ORDER BY id DESC', ts_start, ts_end)

Keep in mind that alerts are deleted automatically, make sure that you've set the limit correctly in Utilities > General configuration.