I was making some scheduling changes. This amounted to some crontab entry modifications. I do thing very rarely. It happens maybe once or twice a year at most. I took a look at the current settings. Needed to changes some tasks to run on Tuesday instead of Wednesday.
Now I don't know the crontab entry syntax by heart. When memorize that when you can look it up? At this point I also figured why look it up if you can reverse engineer it by looking at some entries. I saw some existing entries that run on Tuesdays. Then I saw some existing entries that run on Wednesdays. The first difference I noticed was that the Tuesday jobs started with a 0 on the crontab line, and the Wednesday jobs started with a 1.
I figured this was simple. Just change the first digit to a 1 and you move the job to Wednesdays. However I had a nagging feeling in my stomach. Why would they define Tuesday as 0? Shouldn't 0 represent the start of the week? That would make Sunday be represented by 0. Or if they were really weird, maybe Monday could be 0. But not Tuesday.
I decided to look up the cron docs. Oh snap. That first parameter is minute of the hour when the job is supposed to fire. Parameter number 5 on the line governs the day of the week when the job is kicked off. Good thing I did not rely too heavily on my weak reverse engineering skills. The moral of the story is to look stuff up unless it cannot be easily Googled.
Work Smarter not Harder
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We have large data sets in my current project. Every year tons more data is
loaded into the system. So we only keep the majority of data for 4 years.
After...