What is the benefit of using Externally Described files
over Internally
Described?
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Answer / manoj
I think Externally described files can be used in any
program.
Internally described files can only be used within that
internally defined program.
| Is This Answer Correct ? | 15 Yes | 2 No |
Answer / narender
Well when you create any data base file( eg PF) using the
STRSEU and save and compile the file you will get the DDS
called Data Description Specification of that file. The
file which have the DDS is called Externally Described file
and it must exists before you use it in any program. The
file for which no DDS exist are called Internally or
Programed described files. These files are defined in the
program itself along with the data fields so it needs some
effort in coding also.
| Is This Answer Correct ? | 12 Yes | 3 No |
Answer / remya
Internally described file-A flat file is called internally
or program described file.this flat file can be used in any
program but the fields or structure can be described only
within that particular pgm.
externally described file-Any file that has dds entries or
specified structure is called externally described file.
benefit of externally described file is that we can directly
read, write, update, delete the records of file in the
pgm.but in the case of program described files we can do the
above specified file operation only with the help of a data
structure(except read).
| Is This Answer Correct ? | 10 Yes | 1 No |
Answer / nazi
1. the reusuabaility increases in case of externally
defined files as these can be defined and used in many
programs.
2. a change in the structure of the externally defined file
only causes only the reconpilation of the programs using it
and no other major code change.
| Is This Answer Correct ? | 5 Yes | 1 No |
Answer / nitin
The database which is created outside the program and
declare in program as Externally described. These are PF,
LF which have DDS and and compiled to create a object.
Externally described files are different from Program
described files whose DDS define within program itself.
| Is This Answer Correct ? | 4 Yes | 3 No |
Answer / brian kelly
substantially less coding, consistent field names.
Only need RPG input specs for externally described files if
you are using the cycle with matching records or level
breaks. Even then, you need only specify the fields thata
re involved in the match or the break. No need to describe
output specs for DB files. Can also describe printer files
externally and display files naturally are described
externally in a file object. At compile time, the compiler
sneaks ino the file object and creates input and output
specs from those files that have the RPG "E" switch turned
on in col 19 of RPG/400. Same facility exists in RPGIV in
another column.
| Is This Answer Correct ? | 1 Yes | 0 No |
Externally described files are defined in outside of the pgm
which has specific structure(fields and attributes). So that
you can use in multi program.
Internally described files are defined in inside of the
program or flatfile(fully proc)-without structure.
| Is This Answer Correct ? | 1 Yes | 0 No |
externally described files means we have to use the already
described files somewhere else with in ur file.internally
described mens we are writing entire code with in our
program
| Is This Answer Correct ? | 1 Yes | 1 No |
Answer / nagendra
A FILE IS CREATED WITH FIELD LEVEL DESCRIPTIONS IS KNOWN AS
EXTERNALLY DESCRIBED FILE WHERE IN PROGRAM DESCRIBED FILE WE
WILL ONLY GIVE LENGTH OF THE RECORD EX:FLAT FILE
| Is This Answer Correct ? | 1 Yes | 1 No |
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