I am working in a Natural/Adabas environment.
I have very brief idea about these statemsnts(in subject line).
Can someone elaborate these three statements also publish when to use whaich statement. Which is preferrable in terms of resource consuption and Adabas Calls
The READ statement is used to read records from a database. The records can be retrieved from the database:
in the order in which they are physically stored in the database
(READ IN PHYSICAL SEQUENCE), or
in the order of Adabas Internal Sequence Numbers
(READ BY ISN), or
in the order of the values of a descriptor field
(READ IN LOGICAL SEQUENCE).
The FIND statement is used to select from a database those records which meet a specified search criterion.
The HISTOGRAM statement is used to either read only the values of one database field, or determine the
number of records which meet a specified search criterion.
The HISTOGRAM statement does not provide access to any database fields other than the one specified in the
You usually use READ to read sequentially large number of records by some descriptor.
The FIND is rather for direct access to small amount of records of database.
The HISTOGRAM use only index part of database so it works quickly.