Command Reference Guide

MXCS Commands and Objects
SQL/MX Connectivity Service Administrative Command Reference—526350-005
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MXCS Object Types
MXCS Object Types
MXCS objects that support the command-line interface for SQL/MX connectivity
service are:
Object Ownership Hierarchy
A DS is a named collection of attributes that resides on a disk. A DS instance is a
logical entity in a service that has all attributes of the DS, plus a state. A DS instance
also owns all the servers started by the service that uses it (Figure 2-1
). A server uses
one DS and its EVARS and is owned by one service. One DS owns each defined
environment variable. Each EVAR is an attribute of one DS. Each service has a DS
instance, and several services can use a DS at the same time.
Object Ownership Complexity
Complexity appears when the system has several services and DSs, as shown in
Figure 2-1
. The DS resides on a disk as a set of values and attributes, with the
memory-resident DS instance built in each service from the DS definition on that disk.
When the DS is added, altered, or deleted, all services are notified of the changes, and
each DS instance is updated. EVAR changes are also propagated to all services, but
only to idle servers. Servers with existing connections are not modified.
Two DSs can have an EVAR of the same name, but each EVAR is unique with its own
values.
DS (data source) A named collection of connection attributes for the servers. A DS has
a single definition on a particular system and can be seen by all
services on the system. (A particular DS can be different between
different systems.) The DS instance must be in the started state on
any service that is using it (allowing connections). On any other
service, a specific DS could be in the stopped state.
EVAR
(environment
variable)
A name and value pair defined in the server environment after the
client connects to the MXCS server. Several different EVAR types exit,
each with slightly different syntax. The definition or setting of an EVAR
is per each DS. System-wide settings are not possible.
Server A process that supports client connections to the database. Many
MXCS server processes can run on different CPUs within the system,
each owned by the service the started it. Each server also uses one
DS. However, association and configuration servers are not in the
MXCS server object class.
Service A logical object started by the MXOAS command that always contains
processes for the association server and usually those for the
configuration server also. The service object monitors all DSs defined
on the system and all user connection requests on the first of several
HP NonStop TCP/IP ports assigned to it by the MXOAS command.
User A logical object that defines access permissions for an administrator
of the MXCS configuration database.