Question { 7279 }

Types Of Read , FIND

Answer

FIND- to access one or multiple records using search
criteria .The FIND statement has several forms. The
essential ones are as follows:
• FIND
• FIND NUMBER
FIND and FIND NUMBER are completely different - FIND
retrieves data whereas FIND NUMBER queries the database.

A FIND statement has a processing loop associated with it.

READ- to access one or multiple records with different
keys even if elements of the key are unknown. It has
multiple forms as described below:

READ PHYSICAL - when all or most of the records in the file
are to be presented
(most efficient) when the sequence of records is not
important
when there is no risk of increasing record size during
update
READ BY ISN - when some or all of the records in the file
are to be presented
when the sequence of records is not important (or ISN
sequence is required)
when there is a risk of increasing record size during update
READ LOGICAL - when some or all of the records in the file
are to be presented
(least efficient) when only records within a specific key
range are to be presented
when the sequence of records presented is important

Question { IBM, 20844 }

difference between fetch , call and callnat

Answer

Fetch- calling a natural pgm
CALL- it is used to call another pgm (other then natural)
CALLNAT- calling a natural subpgm
Fatch retrun- it will retrun the contol back

Question { 11224 }

What exactly is a hyperdescriptor? How does it work?

Answer

Hi friends,

I don't know much about hyperdescripto rbut i can tell you
something on this

Its a special kind of discriptor,It is an extension of
Super descriptor and can have maximum of 20 fields.The
hyperdescriptor option can be used to generate descriptor
values based on a user-supplied algorithm.With
hyperdescriptors, “fuzzy” matching is possible; i.e.,
retrieving data based on similar rather than on exact
search criteria. Hyperdescriptors allow multiple virtual
indexes, meaning that several different search index
entries can be made for a single data field.