DOCUMENT:Q174689  22-FEB-2000  [foxpro]
TITLE   :HOWTO: Set a Primary Key to Updateable in a View
PRODUCT :Microsoft FoxPro
PROD/VER:MACINTOSH:3.0b; WINDOWS:2.5,5.0,5.0a,6.0
OPER/SYS:
KEYWORDS:kbcode kbDatabase kbHWMAC kbvfp300 kbvfp500 kbvfp600 KbDBFDBC kbMDAC250

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The information in this article applies to:

 - Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0 
 - Microsoft Visual FoxPro for Macintosh, version 3.0b 
 - Microsoft Data Access Components version 2.5 
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SUMMARY
=======

By default, when creating a view on a table, any field with a primary key index
is not marked as updateable. This article illustrates how you can mark the
primary key as updateable through the View Designer, and programmatically.

MORE INFORMATION
================

View Designer
-------------

To mark the primary key as updateable through the View Designer interface, use
the following steps:

1. Open the view in the View Designer.

2. Click the Update Criteria tab.

3. Click the Update column beside the primary key field.

   NOTE: The Update column has a column header that looks like a pencil. If you
   do not select the Update column and you attempt to INSERT a new record, you
   may receive one of the following errors:

   Connectivity error: [Microsoft][ODBC Visual FoxPro Driver Field
   <fieldname> does not accept null values.

   -or-

   Mandatory not null field - missing or null during insert.

Programmatically
----------------

To mark the primary key as updateable programmatically, use the following steps:

1. Open the Tastrade database in the VFP\Samples\Tastrade\Data folder in Visual
   FoxPro 5.0, or the home(2)+"Tastrade\Data" folder in Visual FoxPro 6.0.

2. Run the following program to create a new SQL view based on the Customer
   table.

         ***********RunFirst.prg***********
         CREATE SQL VIEW MYTEST AS SELECT * FROM CUSTOMER
         DBSETPROP("MYTEST","VIEW","SENDUPDATES",.T.)
         ***********End RunFirst.prg*************

3. Modify the view in the View Designer and note that the primary key is not
   marked for updates.

4. Create a program called MarkPrimary and place the following code in it:

         ************MarkPrimary.prg****************
         PARAMETERS ViewName

         x=ALIAS()
         USE IN 0 &viewname
         PrimKeys = CURSORGETPROP('KeyFieldList',viewname)
         i=1
         remField=PrimKeys
         DO WHILE i <> 0
            nextcomma=AT(remField,",")
            IF nextcomma=0 and len(remfield)=0 THEN
               i=0
               EXIT
            ELSE
               IF nextcomma=0 and LEN(remfield)<>0 then
                  tmpfield=remfield
                  y= DBSETPROP(ViewName + "." + ;
                  tmpField,'Field','UPDATABLE',.T.)
                  i=0
                  EXIT
               ELSE
                  tmpField=SUBSTR(remField,i,NextComma -1)
                  remfield=SUBSTR(remfield,nextcomma + 1)
                  i=nextcomma
                  y= DBSETPROP(ViewName + "." + ;
                  tmpField,'Field','UPDATABLE',.T.)
               ENDIF
            ENDIF
         ENDDO

         SELECT  (viewname)
         USE
         IF NOT EMPTY(x) THEN
            SELECT  (x)
         ENDIF
         **************End MarkPrimary.prg*******************

5. Run the MarkPrimary.prg code by typing the following into the Command
   window:

         DO MARKPRIMARY WITH "MYTEST"

6. Modify the view MyTest in the View Designer and notice that the primary key
   field is now marked for updates.

Additional query words:

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Keywords          : kbcode kbDatabase kbHWMAC kbvfp300 kbvfp500 kbvfp600 KbDBFDBC kbMDAC250 
Technology        : kbHWMAC kbOSMAC kbVFPsearch kbAudDeveloper kbMDACSearch kbMDAC250 kbVFP300bMac kbVFP500 kbVFP600 kbVFP500a
Version           : MACINTOSH:3.0b; WINDOWS:2.5,5.0,5.0a,6.0
Issue type        : kbhowto

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