What is the difference between a Physical File & a Logical?
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Answer / aa
members of physical file contains actual records.. where as
logical file does not contain data, it provides a view of
the data stored in to the physical files. LF contains only
an index to the data stored into the physical files.
Is This Answer Correct ? | 191 Yes | 21 No |
Answer / narender
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.
Is This Answer Correct ? | 48 Yes | 8 No |
Answer / sachin bhuriya
physical file has only one record format and logical file
has one or more record formats
Is This Answer Correct ? | 62 Yes | 30 No |
Answer / mallikarjuna raju.m
pf:physical file is an object of *file it contains orginal
data.
lf:logical file is an object of *file will not contain any
data but it holds the path.
Is This Answer Correct ? | 27 Yes | 12 No |
Answer / 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...
Is This Answer Correct ? | 18 Yes | 7 No |
Answer / godwin sf
Physical files hold the actual data of a database file. The data is written in arrival sequence.
Physical files are not required to have keyed fields. If a physical file has key fields, this is the order that an RPG program will read the data if the File Spec in the program indicates to read the data in keyed sequence.
Also, with a keyed field, an RPG program can CHAIN, SETLL, READE and READP.
A simple logical file is a different view of the physical file. It is actually a list of pointers to the physical file. Most of the time, a logical file is nothing more than a way of accessing the physical file with different key fields.
With the standard AS/400 supplied tools, it is hard to see the logical file. One way is to use the copy file CPYF to copy the logical file to a new physical file. Then, look at the physical file... it will be in the same order as the logical file.
The AS/400 Database is full featured. Logical files can join multiple files and select and create new fields.
Is This Answer Correct ? | 12 Yes | 1 No |
Answer / swagga refic
The difference between logical and physical file organisation is that in physical file organisation contains data and have only one record format where as logical file organisation is a view of physical file organisation which does not contain any data and may be based on one physical file or more than one physical file.
(N.B) Logical can be non join or join logical file. Performance becomes better if you use the logical file in the program.
Is This Answer Correct ? | 8 Yes | 3 No |
Answer / harish
Physical path: is Nothing But "Exact location"
Ex:-When ever we upload the file on that time we click
browse option and then we have to go where the file is ..
Logical path: is not a exact location
whenever we download the file on that time we have ask save
the file that is the logical path
Is This Answer Correct ? | 6 Yes | 1 No |
Answer / pavan krishna
physical file is the actual data stored in the hard
disk.whereas logical file actually doesn't exist.os
asssumes everything as a file.so that the files were
introduced in to data bases.
Is This Answer Correct ? | 5 Yes | 2 No |
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