What is the difference between a Physical File & a Logical?

Answer Posted / sujanindian

Physical file (PF) contains the data and have only one
record format. Logical file (LF) is a view of the physical
file which does not contain any data may be based on one
physical file or more then one physical file. Logical file
can have more then one record format. Logical can be non
join or join logical file. Performance becomes better if
you use the logical file in the program. We can able to update
in nonjoin logical files.In the case of join logical files
we can't able to update..
types of nonjoin(3) - simple,mulitple physical files,
multiple record format.
types of joins(3)- inner or simple join or nature join or
missing secondaries, leftouterjoin, selfjoin...

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