SQL/MX 2.x Installation and Management Guide (H06.10+, J06.03+)

Managing an SQL/MX Distributed Database
HP NonStop SQL/MX Installation and Management Guide—544536-007
13-6
Naming Network Nodes
nodes can execute DML and DDL statements and utility commands on the objects just
as the original node can.
Because of transparency, users need not be aware of what node they are executing on
or where metadata or user data is located.
Security Guidelines
•
Access to a remote node in an Expand network—including access to distributed
SQL/MX database objects and registered catalogs—requires successful remote
password validation.
•
Successful remote password verification is also required for the executing user ID
of any command that creates or accesses metadata or user data on a remote node
or that starts a process on a remote node.
•
The security mechanisms enforced for ANSI objects on the local node are also
enforced for distributed ANSI objects.
•
Only the person who creates and owns the catalog or the local super ID user can
register or unregister catalog references from nodes.
Local Autonomy
If a query requires data only from the node on which it executes, the query succeeds
regardless of the availability of remote nodes on which the query’s accessed objects
have partitions. For SQL/MX Release 2.x, query compilation and late name resolution
of ANSI names require access to the nodes on which the accessed objects’ definition
schema exist.
For more information about local node autonomy for SQL/MX Release 2.x, see
Maintaining Local Autonomy in a Network for SQL/MX Release 2.x on page 13-12.
Naming Network Nodes
After an SQL/MX database node has been installed and initialized, do not attempt to
change the node name or number. The node name is recorded in the system metadata
entries and is entered in the file labels throughout the database. The node number is
recorded in the file labels.
Naming SQL/MX Database Objects
SQL/MX database objects have location-independent ANSI names. The database
objects themselves are represented by Guardian files on disk. The correspondence
between ANSI names and Guardian file names is stored in SQL/MX metadata.
Note. Do not attempt to change the node name or node number. Choose node names and
numbers carefully so that you do not need to change them.