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

Working With KeySequenced Files in a UDB Pair
Working With Files
106160 Tandem Computers Incorporated 12–79
Working With Key-
Sequenced Files in a
UDB Pair
The structure of records in a key-sequenced file is briefly described earlier in this
section. This subsection describes how to work with key-sequenced files in a UDB
pair from an NCL process:
How to create the key-sequenced files in a UDB pair from an NCL process
How to open a UDB pair for system-wide access from an NCL process
How to open a UDB pair for use by an NCL process and specify how data is
organized
How to add a record to a UDB pair
How to get (retrieve) a record from a UDB pair
How to put (update) a record in a UDB pair
How to delete a record in a UDB pair
Complete examples of NCL procedures that work with UDB pairs are included at the
end of this subsection.
Working with single key-sequenced files is discussed earlier in this section.
Creating the Files in a UDB
Pair
You can use FUP to create the two key-sequenced files in a UDB pair. The following
values in the two key-sequenced files must be identical:
Record length
Key length and offset of primary keys
Key length and offset of alternate keys (if present)
Additionally, the value of the primary key offset must be zero (0).
Opening the UDB Pair for
Access by NonStop
NET/MASTER MS
The UDBCTL OPEN command opens a UDB pair for access by NonStop
NET/MASTER MS. The first file you specify in the UDB pair is opened by default for
both read and write access; the second (always) for read-only access.
Opening the UDB Pair for
Access by NCL
The FILE OPEN verb opens a UDB pair for access by NCL. You can open the
key-sequenced files in a UDB pair as mapped, unmapped, or delimited.
Note See the discussion on opening a single key-sequenced file for access by NCL, earlier in this section, for
information on opening a UDB pair for access by NCL.