NET/MASTER Network Control Language (NCL) Programmer's Guide

Controlling Access to UDBs by NonStop NET/MASTER MS
Working With Files
106160 Tandem Computers Incorporated 12–11
access the UDB or UDB pair, and provides a logical connection between NCL and a
UDB or UDB pair.
When you open a single UDB, the UDB ID refers to one file. When you open a UDB
pair, the UDB ID refers to both files, which are treated as a single unit.
A UDB ID must be from one through eight characters long. You can use the following
characters in a UDB ID, as long as the first character is not a digit:
Alphabetic characters: A through Z and a through z
Numeric characters: 0 through 9
Other characters: # $ @ _
The following examples show valid UDB IDs:
INPUT_1
OUTPUT_10
UDBID_$3
NCL#4
You can assign a UDB ID to a UDB or UDB pair either when you make it known to
NonStop NET/MASTER MS, by using the UDBCTL OPEN command, or afterward.
Assigning an Identifier When a UDB or UDB Pair Is Opened. If you assign a UDB ID when
you open a UDB or UDB pair, NCL can work with the UDB or UDB pair immediately.
You use the ID operand of the UDBCTL OPEN command to assign an identifier.
The following example assigns the identifier UDBID1 to the UDB MYFILE when you
open the UDB:
UDBCTL OPEN=$DATA.SUBVOL.MYFILE ID=UDBID1
The following example assigns the identifier UDBID1 to the UDBs MYFILE1 and
MYFILE2 when you open the UDB pair:
UDBCTL OPEN=($DATA.SUBVOL.MYFILE1,$DATA.SUBVOL.MYFILE2)
ID=UDBID1
You can use an asterisk (*) as the qualifier to the ID operand. For a single UDB,
NonStop NET/MASTER MS uses the unqualified part of the UDB name as the
UDB ID. For a UDB pair, NonStop NET/MASTER MS uses the unqualified part of the
second file name as the UDB ID.
The following example assigns the identifier MYFILE to the UDB MYFILE when you
open the UDB:
UDBCTL OPEN=$DATA.SUBVOL.MYFILE ID=*
The preceding example is the same as the following example:
UDBCTL OPEN=$DATA.SUBVOL.MYFILE ID=MYFILE