Server Agent Administration

Oracle

When configuring an Oracle database agent the critical configuration items are:

• Database Identification - this is an actual Oracle System Identifier (SID) e.g "ORCL", which identifies the actual Oracle environment that you want to be connected with. This is the value that you enter into the "Database Name" field of either your Admin Assistant's database agent configuration form or wizard dialog. If you choose to have database identification take at the client rather than server, you enter this value into the "Database Name" field or connection attribute when configuring your OpenLink client.

Oracle provides a number of environment variables for configuring database clients, the basic set required for successfully connecting your database agent to an Oracle database server are tabulated below:

Table: 1. Default Rule Book settings

Rule Book Section & parameters	Default Rule Book Settings	Notes
[Environment ORACLE7]
ORACLE_HOME	/ dbs/oracle7	The home directory for the Oracle installation.
ODBC_CATALOGS	Y	Uncomment after loading the "odbccat7.sql" script.
MULTIPLEX_LDA	5	Allow 5 OpenLink clients via a single database session
OPL_USER_TBLS_FIRST	N	set to Y to show OpenLink User Tables first
SHOW_REMARKS	N	Set to Y to retrieve SQLColumns REMARKS field
[Environment ORACLE8], [Environment ORACLE9]		Parameters are common in Oracle 8 and 9i
ORACLE_HOME	/ dbs/oracle8 or /dbs/oracle9	The home directory for the Oracle installation.
ODBC_CATALOGS	Y	Uncomment after loading the "odbccat8.sql" script.
MULTIPLEX_LDA	5	Allow 5 OpenLink clients via a single database session
OPL_USER_TBLS_FIRST	N	set to Y to show OpenLink User Tables first
SHOW_REMARKS	N	Set to Y to retrieve <nopSQLColumns REMARKS field
OCI_PREFETCH_ROWS	120	Sets the number of rows to be prefetched
OCI_PREFETCH_MEMORY	64	Kb of memory allocated for rows to be prefetched

Database Agent Specific Settings

The "odbccat.sql" scripts explained:

These scripts exist for each version of Oracle supported, the files "odbccat6.sql", "odbccat7.sql", and "odbccat8.sql" representing Oracle versions 6 up to version 8 respectively. Oracle 9i can use the "odbccat8.sql" script. These scripts are to be applied to your Oracle instance to enable efficient and extended functionality between OpenLink and Oracle when handling ODBC, JDBC, UDBC, and OLE-DB catalog calls such as SQLForeignKeys() and QLPrimaryKeys() functions. These functions have significant impact on the performance of your OpenLink clients.

To run these scripts you need to start the Oracle server manager (svrmgr or sqldba if you do this from the command line). Connect as internal and run the script by locating the relevant script file as you would any other Oracle SQL script file.

Rebuilding Oracle Database Agents

OpenLink provides a relinkable library and script files that enable you to rebuild your database agents as shared, as opposed to statically linked binaries, or for the purposes of getting a closer database implementation fit if your Oracle database environment is a more recent release than the actual version used by OpenLink to build the database agent installed on your system. Please read the Relinking OpenLink Database Agents section that follows, for details on how to perform this task.

Application Server & 3-Tier Architecture Configuration

There may be situations in which you are unable to install your OpenLink Request Broker and Database Agents on the same machine as the one hosting your Oracle database server. Irrespective of the reasons that lead you to this scenario, it is possible to configure your OpenLink database agents hosted on your Application Server machine such that they connect to a remote Oracle database on your Database Server machine using Oracle database specific networking (SQL*Net or Net8) as opposed to OpenLink's Database Independent Networking. The end result being a 3-tier distributed OpenLink architecture in which the communication between OpenLink clients and database agents use OpenLink Database independent Networking, while the communication between the Oracle database agent and the Oracle database server uses Oracle SQL*Net or Net8.

Configuration Steps:

Assuming you have an Oracle Database Server machine called "mainserver2" that has an Oracle Listener process running, you would enter the following (presuming that your SQL*Net or Net8 alias for this Listener is also named "mainserver2"):

1. On your Application Server (the machine hosting your database agents) create a SQL*Net or Net8 Alias named "mainserver2" (for purposes of this example only).

2. Ensure that you have a usable connection to the remote Oracle database server using the SQL*Net or Net8 alias "mainserver2"

3. Add the following values to the "Server Options" field within the Admin Assistant Forms or Wizards used to configure your database agent. If you choose to set this value on the client simply enter the same value into to the "Database Name" Attribute associated with the configuration of your OpenLink client (see OpenLink ODBC or JDBC or UDBC client configuration for more details):

      mainserver2

See Also:

Application Server Architecture for various illustrations of distributed client-server architectures supported by 

OpenLink database agent

Unicode Configuration

See the Unicode section? for configuration details.