Greg Spiegelberg wrote:
The reason for my initial question was this. We save changes only. In other words, if system S has row T1 for day D1 and if on day D2 we have another row T1 (excluding our time column) we don't want to save it.
It still isn't entirely clear to me what you are trying to do, but perhaps some sort of calculated checksum or hash would work to determine if the data has changed?
Best example I have is this.
You're running Solaris 5.8 with patch 108528-X and you're collecting that data daily. Would you want option 1 or 2 below?
Option 1 - Store it all Day | OS | Patch ------+-------------+----------- Oct 1 | Solaris 5.8 | 108528-12 Oct 2 | Solaris 5.8 | 108528-12 Oct 3 | Solaris 5.8 | 108528-13 Oct 4 | Solaris 5.8 | 108528-13 Oct 5 | Solaris 5.8 | 108528-13 and so on...
To find what you're running: select * from table order by day desc limit 1;
To find when it last changed however takes a join.
Option 2 - Store only changes Day | OS | Patch ------+-------------+----------- Oct 1 | Solaris 5.8 | 108528-12 Oct 3 | Solaris 5.8 | 108528-13
To find what you're running: select * from table order by day desc limit 1;
To find when it last changed: select * from table order by day desc limit 1 offset 1;
I selected Option 2 because I'm dealing with mounds of complicated and varying data formats and didn't want to have to write complex queries for everything.
Greg
-- Greg Spiegelberg Sr. Product Development Engineer Cranel, Incorporated. Phone: 614.318.4314 Fax: 614.431.8388 Email: [EMAIL PROTECTED] Cranel. Technology. Integrity. Focus.
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