INF: Description of Btrieve
  
PSS ID Number: Q114505
Article last modified on 03-13-1995
 
1.00 1.10 2.00
 
WINDOWS
 

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The information in this article applies to:
 
 - Microsoft Access versions 1.0, 1.1, and 2.0
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SUMMARY
=======
 
Btrieve is not a full, stand-alone database application like Microsoft
Access or Microsoft FoxPro. This article describes how Btrieve works with
Microsoft Access and with Novell NetWare and non-NetWare networks.
 
MORE INFORMATION
================
 
Btrieve is not a full, stand-alone database program like Microsoft Access
or Microsoft FoxPro. Btrieve is a dynamic-link library (DLL), similar in
nature to a terminate-and-stay-resident (TSR) program in MS-DOS, that
provides the ability to read from and write to database files on a hard
disk. It is a record-managing engine only and does not have a user
interface.
 
You can attach Btrieve databases in Microsoft Access, or import data from
or export data to Btrieve databases. To use Btrieve without Microsoft
Access, you must first write a program (commonly known as a front end) to
access the Btrieve functions. These function calls specify the operation
you want the Btrieve engine to perform, and also send any necessary data.
 
Since Btrieve handles all data as complete and separate records, it does
not consider the actual contents of the records. To Btrieve, it is just
writing information to the hard disk. The only exception to this behavior
is when Btrieve deals with the portion of the record that has been
identified as an index. In this case, Btrieve uses this portion of the
record to create a binary tree index, which is sorted according to the
method applicable for the type of data it contains.
 
Non-NetWare Usage of Btrieve
----------------------------
 
In MS-DOS, Btrieve is accessed as a TSR whose functions are called by
interrupts made by the front end. The function performs the requested
operation on the specified file and then returns control to the front end.
 
In Microsoft Windows, Btrieve is accessed as a DLL named WBTRCALL.DLL.
This DLL contains the same functionality as mentioned above, except that
the parameters are passed directly.
 
NetWare Usage of Btrieve
------------------------
 
Btrieve is integrated into Novell NetWare networks and is used internally
by NetWare to create a full client/server environment. This is accomplished
by loading Btrieve on a server as a NetWare Loadable Module (NLM), and then
making function calls to the NLM over the network. Doing this requires a
combination of a TSR and a DLL.
 
The TSR is BREQUEST.EXE on the client (workstation). BREQUEST.EXE is a
network communication package that must be loaded before starting Windows,
and is activated by WBTRCALL.DLL. This version of WBTRCALL.DLL differs from
the one used in non-NetWare environments, even though they have the same
name. This DLL's only function is to activate the TSR, which in turn sends
the parameters across the network to the server. Where multiple servers are
used, Novell provides routers to connect them together so that only one
copy of Btrieve must be loaded on the main server.
 
Btrieve is manufactured by Novell Inc., a vendor independent of Microsoft;
we make no warranty, implied or otherwise, regarding this product's
performance or reliability.
 
Additional reference words: 1.00 1.10 2.00 Attaching
KBCategory: kb3rdparty
KBSubcategory: IsmBtrv
 
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Copyright Microsoft Corporation 1995.
