README.TXT

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                MICROSOFT SQL WORKSTATION 6.0 
          DB-LIBRARY FOR VISUAL BASIC SAMPLE PROGRAMS 
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This file tells about the DB-Library for Visual Basic sample 
programs included with Microsoft(R) SQL Workstation 6.0. The 
information in this file supplements the information in your  
Microsoft SQL Workstation documentation. 
 
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DB-LIBRARY FOR VISUAL BASIC SAMPLE APPLICATIONS 
 
DB-Library for Visual Basic provides a set of sample applications 
that demonstrate the use of many DB-Library for Visual Basic functions 
and routines. 
 
You can use the code in these sample applications as models or 
templates for your own applications. By cutting and pasting code from 
specific application files, by using global procedures from the sample 
common code files, and by including the declarations for those 
procedures from the sample include files, you can quickly create the 
foundation for your own applications. 
 
The QUERY sample application demonstrates the following SQL Server  
operations. Each sample: 
* Logs in and opens a connection to SQL Server from the client. 
* Allows a user to choose which database to use. 
* Allows the user to send a query to SQL Server. 
* Accepts results from SQL Server and returns the results to the user. 
* Closes the SQL Server connection. 
* Exits the application. 
* Handles any errors or messages generated by these operations. 
 
The rest of this file describes the contents of all of the Project 
files used by the QUERY sample application. This information is 
organized by the names of the subdirectories in which each Project 
file resides. 
 
Once you are familiar with the QUERY sample applications and their 
use of the common code directories, refer to the other sample 
applications provided for examples of implementing additional 
SQL Server features. 
 
COMMON CODE 
 
The files in the subdirectory DBLIB\VSAMPLES\COMMON contain general 
code that can be used by all DB-Library for Visual Basic applications. 
The QUERY sample application include all of the COMMON files with  
their Project files and invoke the procedures that these files contain. 
The following sections describe the files contained in the COMMON 
subdirectory. 
 
The VBSQLGEN.BAS File 
The VBSQLGEN.BAS module defines a set of procedures that perform tasks  
common to most DB-Library for Visual Basic applications. Such tasks 
include: 
* Opening and closing a SQL Server connection 
* Processing SQL queries  
* Executing SQL commands  
* Displaying error messages  
 
The LOGIN.FRM File 
The LOGIN.FRM file calls a subroutine in the VBSQLGEN.BAS module that 
uses DB-Library for Visual Basic functions to open a SQL Server 
connection and log in users. The code for logging in users is used in 
all of the sample applications except the browse-mode example. 
 
The CHNGDB.FRM File 
The CHNGDB.FRM file uses the DB-Library for Visual Basic function 
SqlUse% to change the current database to a database name supplied 
by the user. The code for changing databases is used in all of the 
sample applications. 
 
THE WINCODE DIRECTORY 
 
The files in the DBLIB\VSAMPLES\WINCODE subdirectory contain code 
that is available for use by all applications. To use the common code, 
you can add the files to a Visual Basic Project or you can copy the 
code from these files into an existing file. The following sections 
describe the files in the WINCODE subdirectory. 
 
INIEXITW.BAS 
INIEXITW.BAS contains DB-Library initialization and exit code. 
 
RESULTSW.BAS 
RESULTSW.BAS contains procedures for handling compute rows and stored  
procedure output parameters. These procedures are called by the  
Process_Sql_query procedure defined in VBSQLGEN.BAS. 
 
THE VBQUERY DIRECTORY 
 
The directory DBLIB\VSAMPLES\QUERY include the project make file for 
the sample application and the sample application's primary, or 
startup, form, VBQUERY.FRM. 
 
VBQUERY.BAS and VBSQL.BAS 
VBQUERY.BAS and VBSQL.BAS contain the global definitions for this  
application. They include the relevant variable definitions from 
GENGLOB.BAS. These are required. The VBSQL.BAS file contains the 
global definitions for VBSQL functions and constants. 
 
ADDITIONAL SAMPLE APPLICATIONS 
 
This section provides information about some of the other 
DB-Library for Visual Basic sample applications provided in your 
package. 
 
The TEXT Sample Application 
The TEXT sample application enables users to select text files from 
a database, and view and edit the text in the text file. 
 
The TEXT.FRM file of the TEXT project contains the code of the main 
form of the application. It includes subroutines for selecting,  
retrieving, and editing text files. For example, the LoadText 
subroutine contains DB-Library for Visual Basic functions that read 
text fields from database tables; the InsertText subroutine contains 
DB-Library for Visual Basic functions that insert text into database 
text tables. 
 
The IMAGE Sample Application 
The IMAGE sample application enables users to select image files from 
a database, view images, and add images to a database. It looks and 
works much like the preceding TEXT sample application. 
 
The IMAGE.FRM file of the IMAGE project contains the code of the 
main form of the application. It includes subroutines for selecting, 
retrieving, and adding image files. For example, the LoadImage  
subroutine contains DB-Library functions that read images from  
databases; the InsertImage subroutine contains DB-Library functions 
that insert images into databases. 
 
The BROWSE Sample Application 
The BROWSE sample application demonstrates the use of DB-Library 
for Visual Basic browse-mode functions. The BROWSE project uses the 
common code files VBSQLGEN.BAS and ABOUT.FRM. The code from the 
GENGLOB.BAS file is included in the BROWSE.BAS global file. 
 
The BLOGIN.FRM file includes the code from the common code file 
LOGIN.FRM. However, because the browse mode requires two SQL Server 
connections, the code to open a connection is repeated. The 
OK_BUTTON_Click subroutine of the BLOGIN.FRM file illustrates the 
correct way to open SQL Server connections for browsing. 
 
The BROWSE.FRM file of the BROWSE project contains the code of 
the main form of the application. It includes subroutines for 
selecting, retrieving, and updating rows of information. For example, 
the Select_Button_Click subroutine sends a command to query 
SQL Server and processes the results of the query; the  
Update_Button_Click subroutine sends a command to update or change  
information in results rows; the ProcessResultRow subroutine  
processes the data in a results row. This subroutine is used in  
the Select_Button_Click subroutine mentioned previously. 
 
The CURSORS Sample Application 
The CURSORS sample application illustrates the use of cursors in 
DB-Library for Visual Basic applications. The CURSORS project uses 
the common code files VBSQLGEN.BAS, and LOGIN.FRM. The code from  
the GENGLOB.BAS file is included in the CURSORS.BAS global file. 
The CURSORS.FRM file of the CURSORS project contains the code of  
the main form of the application. It includes subroutines for  
opening and closing cursors, fetching rows of data, updating rows,  
and displaying rows. 
 
The RPC Sample Application 
The RPC sample application shows the use of SqlRpcSend% and related 
calls. This sample invokes stored procedures directly (not through 
a language command) and retrieves return status and output  
parameters. Direct invocation of stored procedures is especially  
useful with Open Data Services applications. The sample also shows 
the use of SqlServerEnum% for listing available servers. 
 
The RPC sample application contains most of the stored procedure 
calls in the RPC.FRM module. The RPCLOGIN.FRM file shows the use of  
SqlServerEnum%. RPC return status and output parameter handling are  
covered in RESULTSW.BAS, called by the Process_Sql_query function  
in VBSQLGEN.BAS. 
 
The PUBS Sample Application 
The PUBS sample application is a full-featured application showing 
how many VBSQL functions can be combined into a business application. 
This sample shows a data entry and query form for the authors in  
the pubs database. It illustrates the use of a list box for  
maintaining a key set of records, browse mode for optimistic  
concurrency, and building SQL statements based on data entered. 
It also shows techniques for using Visual Basic features such as  
MDI child windows and grid controls within an application.