17.10 - Maximum Number Of Sessions for a Single Process - Call-Level Interface Version 2

Teradata® Call-Level Interface Version 2 Reference for Workstation-Attached Systems

Call-Level Interface Version 2
Release Number
Release Date
October 2021
Content Type
Programming Reference
Publication ID
English (United States)

Usage Notes

The Maximum Number Of Sessions field specifies the maximum number of sessions that the application program is allowed to have running concurrently on database computers.

Language Variable Name
C: DBCAREA.H: max_num_sess
Routine Action Taken
DBCHINI: reads
DBCHCL: ignores
Used by Action Taken
application program none

The value of zero indicates that DBCHCL is to use the default value from the SPB for the Maximum Number Of Sessions. The maximum possible value for this field is system-dependent, that is, limited to the number of open file descriptors a process is allowed.

The application program generates sessions on more than one database computer, the application still cannot have more than Maximum Number Of Sessions, in total, running concurrently.The application program calls DBCHCL for the Connect function when it already has Maximum Number Of Sessions logged on, the return code from DBCHCL will be non-zero.

The default value of Maximum Number of Session, which is 300, can only be changed by an application by setting the max_num_sess field in the clispb.dat file. If this DBCAREA field is set, CLI ignores this field.