SQL/MX 2.x Installation and Management Guide (G06.24+, H06.03+)

Managing an SQL/MX Distributed Database
HP NonStop SQL/MX Installation and Management Guide—523723-004
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Naming SQL/MX Database Objects
NonStop SQL/MX resolves these ANSI names to the corresponding underlying
Guardian file names.
ANSI Names
SQL/MX database objects have three-part, location-independent ANSI names of the
form catalog.schema.object. Location independence means that there is no
identification of the node or volume on which an SQL/MX database object exists.
SQL/MX objects that reside on one node and are accessed from other nodes must be
visible from those other nodes. Use REGISTER CATALOG to register a catalog on
remote nodes. The objects of a catalog registered on a remote node are accessible
from that node.
A location-independent ANSI name is not always unambiguous within a network. It is
possible and legitimate for each of two nodes in a network (\A and \B) to have a
catalog with the same name (for example, CATX). Each node can access its own
catalog CATX and the database objects in it by using location-independent ANSI
names. However, node \A cannot access anything in the catalog CATX on node \B,
and vice versa.
Guardian Names
The Guardian files that represent SQL/MX database objects follow these naming rules:
•
They reside in protected subvolumes with names that start with the letters ZSD.
DP2 prevents the creation of non-SQL/MX files in these subvolumes. The
subvolume name is exactly eight characters, except for the ZSD0 and ZSD1
subvolumes used for the system and MXCS schema, which are four characters.
•
The file name part of Guardian files that represent SQL/MX objects is exactly eight
characters and ends with the digits 00 or 01.
•
All database objects in a schema are represented by Guardian files with identical
subvolume name parts, referred to as the schema subvolume. These files can
occupy multiple volumes distributed across nodes in an Expand network.
•
Each schema has a schema subvolume name that starts with the letters ZSD. You
can specify subvolume and file names on certain statements, like CREATE TABLE.
The file and subvolume names used follow the preceding rules. If you do not
specify the Guardian file and subvolume names, NonStop SQL/MX automatically
generates those names. To avoid incidentally meaningful but undesirable names
(for example, ZSDHELL0.SMARTY00), vowels and the digit zero are never used in
generated portions of names. While user-supplied names must conform to the
other Guardian naming rules, they can contain vowels and the digit zero.
Note. For information about naming SQL/MP database objects, including guidelines on using
DEFINEs for network objects names, see the SQL/MP Installation and Management Guide.