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DETERMINE; (DT) Commands
DETERMINE; (DT) Commands
The DETERMINE; command variants are used to read data into memory from the LINC
database through a Profile or, using DETERMINE; ACTUAL, an Extract file or dataset.
The particular variant controls the manner in which records are read into memory, and
how many. Once a record is in memory, it can be manipulated by the associated logic.
The definition of the Profile, in particular its Ordinates and ASCENDING; or
DESCENDING; Profile Attributes, determine which records are retrieved, and the order in
which the records are retrieved.
Caution
There are differences in the way in which database accesses are handled on the
various host types.
For MCP based LINC Systems and UNIX Griffin LINC Systems, accesses by
DETERMINE; commands are dependent on the positioning of the Profile by nested
DETERMINE; commands. To avoid unexpected side-effects do not access the
sameProfilewithnestedDETERMINE;commandsasaccessesbynested
DETERMINE; commands can alter the positioning on the Profiles required by outer
DETERMINE; commands, and unexpected records can be read.
For OS 2200 based LINC Systems and UNIX ORACLE LINC Systems, each
DETERMINE; command is independent of previous positioning.
For LDA, the behaviour matches that of the target host defined by the TargetHost
parameter in your LINC.INI file.
Variants of the DETERMINE; Command
The particular variant controls the number and manner in which records are read into
memory. Once in memory, a record may be manipulated by logic.
The DETERMINE; command variants are summarized in the following table, and are then
described in detail in the following subsections.
Variant Summary of Function
DETERMINE; ACTUAL Creates a loop in which all records are read in order from a Profile,
Extract file, or Component
DETERMINE; BACK Creates a loop in which all the records are read in reverse Profile
order, starting from specified values
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