Describe file organisation?
A file is organized logically as a sequence of records. These records are mapped onto disk blocks.
A) Fixed-Length Records
Type deposit=record
Accountnumber:char(10);
branch name:char(22);
balance: real;
end
B) Variable length records
a) storage of multiple record types in a file
b) Record types that allow variable lengths for one or more fields
c) Record types that allow repeating fields
d) Byte string Representation
e) Fixed length representation
- Reserved space
- List representation