I have a tablespace that has a datafile of 400m and out of which 300m has been used.
Assuming that I add another datafile (of 200m) to the tablespace, is the remaining 100m left from the 300m going to be used before the new 200m that I have added will be used?
I am thinking that if I go ahead and add the new datafile of 200m, then the 100m that is remaining out of the 400m will not be used.
Can any one please explain?

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