Understanding Client Requesters
A workstation that needs to access database files is considered a client to the machine running the PSQL Server. A piece of software called a client requester, or requester for short, is required to access database files from a PSQL database server. Your application’s PSQL calls go through the requester, which sends them to the PSQL Server for processing and then returns the reply to your application.
Refer to the release notes provided with the product for a list of the platforms on which PSQL requesters are supported. The requesters use the TCP, SPX or NetBIOS protocols to communicate with the server MicroKernel, depending on the type of server you have. Ensure that your workstation has the appropriate network protocol software installed.
*Note: Clients using DOS operating systems will have only transactional access to the data files. No relational access is available for this platform.
Types of Windows Requesters
PSQL includes the following types of requesters for Windows:
•
DOS
•
Trace
You do not load or unload the Requester explicitly; the system loads the Requester with the first application call to PSQL and unloads the Requester when you exit your application.
DOS Requesters
This type of requester is used for applications that run under the DOS operating system.
Trace Requesters
Trace requesters are used for troubleshooting (tracing) client problems at a low level. Generally, you will never need to perform this type of tracing. The low-level tracing is intended for use by trained support staff. Your product vendor or PSQL Support will direct you on how to conduct low-level client tracing, which includes how to use the trace requesters.
Note that the tools provided with PSQL solve most troubleshooting issues. For example, you would run the network connectivity tests in PSQL System Analyzer to verify network connectivity. Also at your disposal is the Knowledge Base at the PSQL website, through which you may search for information about particular client issues.
Where To Go From Here
A proper configuration is essential to smooth operation of your requester software. See Chapter 10, Configuring Network Communications for Clients for detailed information on how to configure PSQL requesters.