Client Server Systems (cont'd)
There are several ways to represent addresses in the database address space:
- Physical Addresses - byte string that let's one figure out
where in the secondary storage the data lives. Might consist of:
- The host to which storage is attached
- An identifier for the disk or device
- The cylinder number
- The track within the cylinder
- The block within the track
- The offset to the beginning of the record
- Logical Addresses - in this scheme each block or record has a logical address
which is a string of bytes of some fixed length. Then a map table is used to look
up where on the disk this corresponds to.