[rrd-users] changing step time?

[Gregory Guthrie]

I started a new database a few weeks ago, and have a few questions;
  
1) What is the actual meaning of "step" - specifically what happens if values are fed in more often?
     The documentation says that if updates are less frequent, they are interpolated (up to heartbeat), but I didn't see this converse case.

2) Can I change step after the database is created?
  - I setup one value for daily step size, but now want to do twice-daily updates.
  - Can I change step size, and just start inserting updates more often?

3) If I were to re-create the database, is there any (easy) way to preserve the data already collected?

4) If I have a few known initial values, can I insert them into a live rrd database using the rrdedit tool?
   I tried to do this using rrdtool, but got this error:
      illegal attempt to update using time 1262354400 when last update time is 1270818003 (minimum one second step)

The database started on 1/1/2010, and I tried inserting some values all after that. Looking at the database (dump) it looks like there are lots of empty slots to patch these into.

Is there somewhere where these sort of usage details are described? 
Thanks.
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Gregory Guthrie
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