HOWTO: Update a SQL Server Text Field Through a View

ID: Q231894

The information in this article applies to:

Microsoft Visual FoxPro for Windows, version 6.0

SUMMARY

There are specific settings necessary when updating a SQL Server text field using a Visual FoxPro Remote View if you are accessing the text field through a SQL Server View.

NOTE: This only works correctly in Visual FoxPro 6.0 with Service Pack 3 installed.

MORE INFORMATION

When setting up a remote view to a SQL Server view that has a text field in the SQL Server view, it is important to remember that there are specific settings that will make updating the text field fail.

If you do not set the view property CompareMemo to Off, the following settings for the SQL Where Clause Includes causes an update to the text field to fail:

Key and Updateable Fields

Key and Modified Fields

These settings succeed with the Compare Memo property set to true or false

Key Fields Only

Key and Timestamp

When the text field is included in the Where clause, the SQL Server ODBC driver uses the WriteText update method. This method will not update a text field in a SQL View, and it returns the following error:

Update Conflict

At this point you can use the following command to clear the changes:


?TABLEREVERT(.T.)

Sample:


CLOSE DATABASES ALL
SET SAFETY OFF
CREATE DATABASE TextTest
CREATE CONNECTION conn1 CONNSTRING 'driver=sql server;server=sphinxsql;' + ;
   'database=pubs;uid=sa;pwd='
myconn=SQLCONNECT('conn1')
IF myconn=-1 then
   MESSAGEBOX("Connection Failed")
   AERROR(myerr)
   DISPLAY MEMORY LIKE myerr
   RETURN
ENDIF

*!* Test for the view in SQL Server.
*!* If it exists, drop it.
iTestForView=sqlexec(myconn,"if exists (select * from sysobjects where name='test1'" + ;
   " and type = 'V')" + CHR(13) + ;
   "   begin" + CHR(13) + ;
   "   drop view test1" + CHR(13) + ;
   "   end")

*!* Test for the table in SQL Server.
*!* If it exists, drop it and recreate it.
iSucc=sqlexec(myconn,"if exists(select * from sysobjects where name='ttest')" + CHR(13) + ;
   "   begin" + CHR(13) + ;
   "   drop table ttest" + CHR(13) + ;
   "   end" + CHR(13) + ;
   "create table dbo.ttest (ID char(10) primary key," + CHR(13) + ;
   "   myTime timestamp,tnotes text)")
IF iSucc=-1 then
   MESSAGEBOX('Create Table Failed')
   AERROR(myerr)
   DISPLAY MEMORY LIKE myerr
   SQLDISCONNECT(myconn)
   RETURN
ENDIF
MyNotes=REPLICATE('This is a test of the emergency broadcast system. ' + ;
   ' If this were an actual emergency, you would be told ' + ;
   ' where in your area to contact for news and additional ' + ;
   'information.' ,50) + CHR(13) + CHR(10) + ;
   'End of Original Memo'+ CHR(13) + CHR(10)

iSucc=sqlexec(myconn,"insert into ttest (ID,tnotes) values ('1',?MyNotes)")
IF iSucc=-1 then
   MESSAGEBOX("Insert Failed")
   AERROR(myerr)
   DISPLAY MEMO LIKE myerr
   sqldisconn(myconn)
   RETURN
ENDIF

iSucc=sqlexec(myconn,"create view dbo.test1 as select * from ttest")
IF iSucc=-1 then
   MESSAGEBOX("Create View Failed")
   AERROR(myerr)
   DISPLAY MEMO LIKE myerr
   SQLDISCONNECT(myconn)
   RETURN
ENDIF

CREATE SQL VIEW MyTest REMOTE CONNECTION conn1 ;
   AS SELECT test1.ID,test1.tNotes FROM dbo.test1
DBSETPROP('Mytest','view','sendupdates',.T.)
DBSETPROP('MyTest','view','WhereType',3)
DBSETPROP('MyTest','view','tables','dbo.test1')
DBSETPROP('mytest.id','field','keyfield',.T.)
DBSETPROP('mytest.id','field','updatable',.T.)
DBSETPROP('mytest.id','Field','updatename','dbo.test1.id')
DBSETPROP('mytest.tnotes','Field','updatable',.T.)
DBSETPROP('mytest.tnotes','Field','updatename','dbo.test1.tNotes')
DBSETPROP('MyTest','view','CompareMemo',.F.)

USE MyTest
BROWSE NOWAIT
UPDATE MyTest SET tNotes=tNotes + "This is added on to the end!"
?TABLEUPDATE()
REQUERY()
MODIFY MEMORY tNotes NOWAIT

To see the error, please comment out the last DBSETPROP line:


DBSETPROP('MyTest','view','CompareMemo',.F.)

REFERENCES

For additional information on SQL Views in SQL Server, search the Index for "Views" in SQL Server Books Online.

For additional information on Visual FoxPro Remote Views, search on "Remote Views" in the Index of Visual FoxPro Books Online.

Additional query words: kbdse

Keywords : kbDatabase kbODBC kbSQLServ kbVFp600 KbDBFDBC kbVS600sp3 kbGrpFox kbDSupport kbCodeSnippet
Version : WINDOWS:6.0
Platform : WINDOWS
Issue type : kbhowto