Full Table Scans and LRU
In a full table scan I understand that the memory block used for a newly read table block is placed at the end of the LRU.
When the second table block is read, is the same memory block replaced?
What I am asking basically is whether for a full table scan only one block in the data buffer is ever used, with the same single block being recycled for the entire content of the table.
Keep in mind that, if you are doing a Full Table Scan, and the CACHE option is not used ( default behavior ) you are not reading one block. You are performing a multiblock operation.
All those blocks are located at the end of the LRU (at the least recently used end of the LRU list in the buffer cache) The consequence of this is that they are immediately flushed from the buffer cache by the next operation ( the same FTS or a different operation )