SESAM/SQL-LINK is a chargeable add-on product of the SESAM/SQL database system. It consists of the following components:
linked-in DBH
the SEDI61L utility (which outputs responses to CALL DML retrieval statements to a SAM file)
the SEDI63L utility (which checks CALL DML statements).
You can use SESAM/SQL-LINK whenever a single application program is to have access to one or more databases. The linked-in DBH then processes the requests of this application program exclusively. It is linked to the application program directly; the program and the linked-in DBH belong to the same task.
SESAM/SQL-LINK is not available for x86 servers.
SESAM/SQL-LINK is only used in its 31-bit variant on all the /390 servers.
Application program and linked-in DBH
The linked-in DBH is loaded and started by the connection module linked to the application program.
Application programs that work with the linked-in DBH must also be linked to the SESLINK connection module (see the “Core manual”). When the first statement is executed, the SESLINK connection module automatically and dynamically loads the modules of the linked-in DBH from the SESAM/SQL module library, provided the module library was assigned appropriately before the application program started.
To ensure that all SESAM/SQL external references are resolved, the application program and SESLINK should be linked statically. SESLINK is already integrated in the SEDI61L and SEDI63L utilities.
The “ESQL-COBOL for SESAM/SQL-Server” and “CALL-DM Applications” manuals describe how an application program is linked and started.
Passing the start parameters
Users who want to use values other than the defaults can parameterize the linked-in DBH by means of the DBH configuration file (see the “ Core manual”). The DBH option LINKED-IN-ATTRIBUTES is used here to make settings specifically for the linked-in DBH.
The configuration file for the DBH start parameters is a SAM file with a freely definable name in which the user enters the DBH start statements and options. The same rules apply to the entry of the DBH start statements and options as apply to the entry of the DBH start parameters in an input file of the independent DBH (see "Entering the DBH start parameters for the independent DBH").
Before the application program is started, the configuration file of the DBH must be assigned with one of the following commands:
With the BS2000 command
ADD-FILE-LINK LINK-NAME = SESCONF, FILE-NAME = configuration_fileWith the SESAM/SQL command (see "Entering the DBH start parameters for the independent DBH")
CONNECT-SESAM-CONFIGURATION TO-FILE = global configuration_file
When the linked-in DBH starts, the start parameters are passed to it.
If one of the configuration-file parameters to be evaluated contains syntax errors, the file is closed and the associated application program receives an error message.
If a configuration file is not assigned before the application is started, the linked-in DBH outputs a system prompt (//). The user can then enter the DBH start statements and options directly on screen.