Posted by Jim Guerber on December 05, 2007 at 01:12:35:
In Reply to: Re: Deleted records posted by Jon Sacks on December 04, 2007 at 14:49:36:
For performance reasons and also stability reasons. When making a newly deleted record, it is sufficient to place the older delete chain pointer into the record, and link it in with one disk write.
It is a uni-directional linked list.
If we were to do FIFO we would have to mark the newly deleted record as deleted and then write the new pointer into the previously deleted record. That would take 2 writes. We would also have to keep 2 delete chain pointers. One pointing to the first and one pointing to the last deleted record.
Sorry about wiping out the first few bytes of the record. We never could figure out a better way.