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

Controlling Access to UDBs by NonStop NET/MASTER MS
Working With Files
12–16 106160 Tandem Computers Incorporated
The following example dissociates the UDB from its identifier:
UDBCTL STOP=UDBID1
After you dissociate a UDB from its UDB ID, you must assign it a new identifier if you
want to make it available to NCL again. The following example assigns the UDB
$DATA.SUBVOL.MYFILE a new UDB ID:
UDBCTL $DATA.SUBVOL.MYFILE=UDBID2
The following example opens a UDB pair and makes it available to NCL by assigning
the UDB pair an identifier:
UDBCTL OPEN=($DATA.SUBVOL.MYFILE1,$DATA.SUBVOL.MYFILE2)
ID=UDBID1
The following example dissociates the UDB pair from its identifier:
UDBCTL STOP=UDBID1
After you dissociate a UDB pair from its UDB ID, you must assign it a new identifier if
you want to make it available to NCL again. The following example assigns the UDB
pair a new UDB ID:
UDBCTL ($DATA.SUBVOL.MYFILE1,$DATA.SUBVOL.MYFILE2)=UDBID2
Reassigning a UDB Identifier to Another UDB or UDB Pair
The ability to associate and dissociate a UDB or UDB pair from an identifier provides
you with considerable flexibility in handling UDBs and UDB pairs. In particular, it
allows you to change the UDBs and UDB pairs that are referred to by an NCL process
without modifying the NCL process.
The following step-by-step example shows how to associate a single UDB with an
identifier, dissociate the UDB from the identifier, and associate another UDB with the
same identifier. (The steps are the same for a UDB pair, except that you must specify
two file names, rather than one, with each UDBCTL command.)
1. Associate a UDB, LOGFILE1, with an identifier, UDBID1, when you open the
UDB, using the following UDBCTL command:
UDBCTL OPEN=$DATA.SUBVOL.LOGFILE1 ID=UDBID1
2. Open another UDB, LOGFILE2, without a UDB ID, using the following UDBCTL
command:
UDBCTL OPEN=$DATA.SUBVOL.LOGFILE2