Definition Attributes
Data Definition Language (DDL) Reference Manual — 426798-002
6- 37
SPI-NULL Clause
When a definition refers to another definition and the referring definition contains one
or more SPI-NULL clauses, these clauses override any SPI-NULL clauses in the
referenced definition. If the referring definition does not have any SPI-NULL clauses, it
inherits the SPI null value or values from the referenced definition. For example:
If a field is sometimes used as an extensible structured token and sometimes for
another purpose, you can define the field with both an SPI-NULL clause and a VALUE
clause. For example:
DEF jobclass TYPE BINARY 16 SPI-NULL 255
VALUE 0.
When JOBCLASS is used as an extensible structured token, the SSNULL procedure
initializes JOBCLASS to the specified SPI null value. When JOBCLASS is used for any
other purpose, DDL initializes it to the initial value specified in the VALUE clause.
DEF assn-ddl-jobcode SPI-NULL 0.
02 prefix TYPE BINARY 16.
02 code TYPE BINARY 16.
END
DEF assn-ddl-jobinfo.
02 jobcode TYPE assn-ddl-jobcode.
02 priority TYPE BINARY 16 SPI-NULL 1.
02 location TYPE BINARY 16.
END
DEF assn-ddl-jobinfo-groups.
02 jobinfo-1 TYPE assn-ddl-jobinfo.
02 jobinfo-2 TYPE assn-ddl-jobinfo SPI-NULL 2.
END
Inherits SPI null value 0
Inherits SPI null value 0
Inherits SPI null value 0
Defaults to SPI null value 255
Inherits jobinfo SPI null values
Overrides group SPI
null values with SPI
null value 2
VST609.vsd