On daily basis I prefer to keep only cron because I always need to run...

On daily basis I prefer to keep only cron because I always need to run repetitive jobs for system administration (log rotation, db defrag, security analisys, ...) and I don't need to run a job once.
Basically AT was maded for running a job once, CRON is for running repetitive jobs (even if you can use it as AT). Both have same features

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