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
13-17
Maintaining Local Autonomy in a Network
If CAT_1 and CAT_2 have few or no interrelations and if the database objects in the
two catalogs are rarely or never accessed by the same application programs or
queries, a configuration like that shown in Table 13-5 might make good sense. In this
configuration, an outage of node \A does not affect metadata access by applications
Table 13-5. Consequences of Network Node Loss, Reconfiguration 2
Node
CAT_1 and
CAT_2
User Data
Present?
CAT_1 and
CAT_2
Metadata
Present?
CAT_1 and
CAT_2
Applications
Present?
Consequences of Losing This
Node on the Other Nodes
\A Yes Yes for
CAT_1
Yes for those
parts that
mainly
access
CAT_1
From nodes \B and \C, you
cannot perform DDL or utility
operations on any of the CAT_2
catalog’s objects, which have
partitions on node \A. You cannot
perform DDL or utility operations
on CAT_1. You cannot perform
dynamically compiled or
automatically recompiled DML
operations on objects in CAT_1.
You cannot perform statically-
compiled DML operations that
require data stored on node \A or
late name resolution of ANSI
names in CAT_1.
\B Yes Yes for
CAT_2
Yes for those
parts that
mainly
access
CAT_2
From nodes \A and \C, you
cannot perform DDL or utility
operations on any of the CAT_1
catalog’s objects, which have
partitions on node \B. You cannot
perform DDL or utility operations
on CAT_2. You cannot perform
dynamically compiled or
automatically recompiled DML
operations on any objects in
CAT_2. You cannot perform
statically compiled DML
operations that require data
stored on node \B or late name
resolution of ANSI names in
CAT_2.
\C Yes No No From nodes \A and \B, you
cannot perform DDL or utility
operations on objects partitioned
across node \C. You cannot
perform statically compiled DML
operations that require data
stored on node \C.