Forms of Extended Global References
There are two forms of extended references:
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Explicit namespace reference — You specify the name of the namespace where the global is located as part of the syntax of the global reference.
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Implied namespace reference — You specify the directory and, optionally, the system name as part of the syntax of the global reference. In this case, no global mappings apply, since the physical dataset (directory and system) is given as part of the global reference.
The use of explicit namespaces is preferred, because this allows for redefinition of logical mappings externally, as requirements change, without altering your application code.
InterSystems IRIS supports two syntaxes for extended references:
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Bracket syntax, which encloses the extended reference with square brackets ([ ]).
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Environment syntax, which encloses the extended reference with vertical bars (| |).
Note:
The examples shown here use the Windows directory structure. In practice, the form of such references is operating-system dependent.
