Forms and Syntaxes

There are two forms of extended references, differing in how they refer to the location of the global:

Explicit namespace reference — This form explicitly includes the name of the namespace where the global is located.
Implied namespace reference — Rather than using the namespace name, this form includes the database directory and, optionally, the system name. In this case, no global mappings apply, because the physical dataset (directory and system) is given as part of the global reference.

Note:

The examples shown here use the Windows directory structure. In practice, the form of such references is operating-system dependent.

Explicit namespace references are preferred, because they allow for redefinition of logical mappings externally, as requirements change, without altering your application code.

For each of these forms of extended references, InterSystems IRIS supports two syntaxes:

Bracket syntax, which encloses the extended reference with square brackets ([ ]).
Environment syntax, which encloses the extended reference with vertical bars (| |).

Bracket Syntax