I've been using RMAN 9i running a cumulative incremental level 1 backup. Of
course naturally there was a level 0 that occurred. Now the fist cumulative
level 1 that occurred the total sizing of the files in total came out to
about 130GB. The second occurrence of cumulative Level 1 the total byte
size came out to 45GB! Am I missing something here? Shouldn't the second
occurrence been >= to the last cumulative level 1 backup in byte size?
Nothing changed as far as db was concerned, except for insertion of data. I
check the rman logs, the views, etc.and everything seemed normal. I was
curious, and decided to try and recover that 2nd backup, and was successful
in recovering the db. Which poses this question from me: why was the 2nd
backup less than 1st? Nothing changed w/ the db, except data was inserted,
and no data deleted. Does Oracle do a double compression (backup set
compressed again into one more backup set) if files reaches a certain
threshold or something?

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