A DBE session is the period between establishing and terminating
a connection to a DBEnvironment by a user or a program. You must
be in a DBE session to execute any of the SQL statements except
the START DBE or CONNECT statements.
You can establish either a single-user DBE session or a multiuser
DBE session for a DBEnvironment. When you have a single-user
session, no other users can connect to the DBEnvironment
for the duration of that session. When you have a multiuser
session, others can access the DBEnvironment at the
same time.
How you establish a DBE session depends on whether the DBEnvironment
is configured to operate in autostart mode.
Autostart is ON by default, but the DBA can reset it by using SQLUtil.
Refer to the "DBA Tasks and Tools" chapter in
the ALLBASE/SQL Database Administration Guide for
more information about using SQLUtil.
Sessions with Autostart |
 |
When the autostart flag for a DBEnvironment has the value
of ON, users with CONNECT authority can start
a DBE session by using the CONNECT statement:
CONNECT TO '../sampledb/PartsDBEC' |
Initiate a single-user session if the DBEnvironment is configured
to operate in single-user mode. Initiate a multiuser session if
the DBEnvironment is configured for multiuser mode.
You can have up to 32 simultaneous DBEnvironment connections.
Sessions without Autostart |
|
When the autostart flag has the value of OFF, a DBA must issue the START DBE statement to make a DBEnvironment accessible.
For example:
START DBE '../sampledb/PartsDBE' |
The START DBE statement illustrated above initiates a single-user
session for the DBEnvironment. To make multiuser access possible,
the MULTI option is specified as follows:
START DBE '../sampledb/PartsDBE' MULTI |
After a DBEnvironment has been started up with the MULTI option, users with CONNECT authority can initiate multiuser sessions as in
the following example:
CONNECT TO '../sampledb/PartsDBE' |
The START DBE statement also lets the DBA temporarily override
several of the DBECon file startup parameters.
Terminating DBE Sessions |
|
To terminate a DBE session, you simply specify the RELEASE statement as shown below:
Using ALLBASE/SQL in a Diskless Cluster |
|
If your workstation is a diskless node in a DUX cluster, the
diskless node should be set up as a client node using ALLBASE/NET.
You cannot CONNECT to a DBEnvironment as if it were on a local disk.
For more information, refer to the ALLBASE/NET User's
Guide.
