DBSHORT - Interpretation of Database Field Short Names

This Natural profile and session parameter can be used to determine the interpretation of database field short names.

A database field defined in a DDM is described by two names:

  • the short name with a length of 2 characters, used by Natural to communicate with the database (especially with Adabas);

  • the long name with a length of 3-32 characters (1-32 characters, if the underlying database type accessed is Db2/SQL), which is supposed to be used to reference the field in the Natural programming code.

Under special conditions, you may reference a database field in a Natural program with its short name instead of the long name. This applies if running in Reporting Mode without Natural Security and if the database access statement contains a reference to a DDM instead of a view.

The decision if a field name is regarded as a short-name reference depends on the name length. When the field identifier consists of two characters, a short-name reference is assumed; a field name with another length is considered as a long-name reference. This standard interpretation rule for database fields can additionally be influenced and controlled by setting the compiler option DBSHORT to ON or OFF:

Possible settings ON Using a short name is allowed for referencing a database field.

However, a data base short name is not permitted in general (even if DBSHORT=ON)

  • for the definition of a field when a view is created;

  • when a DEFINE DATA LOCAL statement was specified;

  • when running under Natural Security.

OFF A database field may only be referenced via its long name. Every database field identifier is considered as a long-name reference, regardless of its length.

If a two character name is supplied which can only be found as a short name but not as a long name, syntax error NAT0981 is raised at compile time.

This makes it possible to use long names defined in a DDM with 2-byte identifier length. This option is essential if the underlying database you access with this DDM is SQL (Db2) and table columns with a two character name exist. For all other database types (for example, Adabas), however, any attempt to define a long field with a 2-byte name length will be rejected at DDM generation.

Moreover, if no short-name references are used (what can be enforced via DBSHORT=OFF), the program becomes independent of being compiled without Natural Security.

Default setting ON  
Dynamic specification yes
Specification within session yes
Applicable statements OPTIONS
Applicable command DBSHORT option of COMPOPT

Examples:

Assume the following data base field definition in the DDM EMPLOYEES:

Short Name Long Name
AA PERSONNEL-ID

Example 1:

OPTIONS DBSHORT=ON
READ EMPLOYEES 
  DISPLAY AA      /* data base short name AA is allowed
END

Example 2:

OPTIONS DBSHORT=OFF
READ EMPLOYEES 
  DISPLAY AA      /* syntax error NAT0981, because DBSHORT=OFF
END

Example 3:

OPTIONS DBSHORT=ON
DEFINE DATA LOCAL
1 V1 VIEW OF EMPLOYEES
  2  PERSONNEL-ID
END-DEFINE
READ V1 BY PERSONNEL-ID 
  DISPLAY AA     /* syntax error NAT0981, because PERSONNEL-ID is defined in view;
                 /* (even if DBSHORT=ON)
END-READ
END