RE: sequential read on full-table scan?

Hi Paul

>Why in the world would Oracle be reading a block at a time rather than
>performing full-table scans?

If Oracle recognizes that a single block has to be read, even while = executing a full table scan, it performs a db file sequential read.

Three common situations lead to multi-block reads that are smaller than = the specified value:

- Oracle reads headers with single-block reads
- Oracle never does an I/O that spans more extents=20
- Oracle never reads a block that is already in the buffer cache

HTH
Chris

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