DOCUMENT:Q310569  31-OCT-2001  [foxpro]
TITLE   :PRB: Using Object.Value in UPDATE - SQL Fails
PRODUCT :Microsoft FoxPro
PROD/VER::3.0,3.0b,5.0,5.0a,6.0,7.0
OPER/SYS:
KEYWORDS:kbDatabase kbSQL kbvfp300 kbvfp300b kbvfp500 kbvfp500a kbvfp600 KbDBFDBC kbGrpDSFox kbD

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The information in this article applies to:

 - Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0, 7.0 
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SYMPTOMS
========

When you use an Object.Object.Value reference in an UPDATE - SQL command, you
may receive the following error message:

   Alias 'object' is not found.

This error occurs only if the Object.Object.Value syntax appears on the right
side of the assignment in the SET clause.

RESOLUTION
==========

To work around this problem, you can find other ways to use the object value.
The sample code in the "More Information" section shows some possibilities.

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

Steps to Reproduce Behavior
---------------------------

1. Run the following code:

   PUBLIC ofrmUpdate

   ofrmUpdate=createOBJECT("frmUpdate")
   ofrmUpdate.Show()
   RETURN

   DEFINE CLASS frmUpdate AS form

      Top = 0
      Left = 0
      Height = 115
      Width = 181
      DoCreate = .T.
      Caption = "Update Form"
      cValue = "NewValue"
      Name = "frmUpdate"

      ADD OBJECT cmdUpdate AS commandbutton WITH ;
         Top = 70, ;
         Left = 5, ;
         Height = 20, ;
         Width = 88, ;
         Caption = "UPDATE - SQL", ;
         Name = "cmdUpdate"

      ADD OBJECT txtValue AS textbox WITH ;
         Value = "Value To Set Field To...", ;
         ControlSource = "ThisForm.cValue", ;
         Height = 23, ;
         Left = 4, ;
         Top = 4, ;
         Width = 154, ;
         Name = "txtValue"

      ADD OBJECT cmdInsert AS commandbutton WITH ;
         Top = 92, ;
         Left = 5, ;
         Height = 20, ;
         Width = 88, ;
         Caption = "INSERT INTO", ;
         Name = "cmdInsert"

      ADD OBJECT cmdBrowse AS commandbutton WITH ;
         Top = 82, ;
         Left = 96, ;
         Height = 20, ;
         Width = 62, ;
         Caption = "BROWSE", ;
         Name = "cmdBrowse"

      ADD OBJECT txtKey AS textbox WITH ;
         Alignment = 3, ;
         Value = 2, ;
         Height = 23, ;
         Left = 160, ;
         Top = 4, ;
         Width = 19, ;
         Name = "txtKey"

      PROCEDURE Load
         CREATE TABLE tblUpdate (cField1 C(25), iField1 I)
         INSERT INTO tblUpdate VALUES ("Hello", 1)
         INSERT INTO tblUpdate VALUES ("GoodBye", 2)
         INSERT INTO tblUpdate VALUES ("So long", 3)
         INSERT INTO tblUpdate VALUES ("Adios", 4)
         INSERT INTO tblUpdate VALUES ("Greetings!", 5)
      ENDPROC

      PROCEDURE cmdUpdate.Click
         *!* The following lines will cause the error.
         UPDATE tblUpdate ;
            SET cField1 = ThisForm.txtValue.VALUE ;
            WHERE iField1 = 2
         *!* UPDATE tblUpdate ;
            SET cField1 = THIS.PARENT.txtValue.VALUE ;
            WHERE iField1 = 2

         *!* The following lines will not cause the error.
         *!* UPDATE tblUpdate ;
            SET cField1 = EVALUATE("THIS.PARENT.txtValue.VALUE") ;
            WHERE iField1 = 2
         *!* UPDATE tblUpdate ;
            SET cField1 = ThisForm.cValue ;
            WHERE iField1 = 2
         *!* UPDATE tblUpdate ;
            SET cField1 =  EVALUATE("THIS.PARENT.txtValue.VALUE") ;
            WHERE iField1 = ThisForm.txtKey.VALUE
         *!* UPDATE tblUpdate ;
            SET cField1 = ThisForm.cValue ;
            WHERE iField1 = ThisForm.txtKey.VALUE
         *!* The following two lines, taken together, do not cause the error.
         *!* loTextbox = ThisForm.txtValue
         *!* UPDATE tblUpdate ;
            SET cField1 = loTextbox.Value ;
            WHERE iField1 = 2
      ENDPROC

      PROCEDURE cmdUpdate.Error
         LPARAMETERS nError, cMethod, nLine
         =MESSAGEBOX("Error in UPDATE command: " + MESSAGE() )
         RETURN
      ENDPROC

      PROCEDURE cmdInsert.Click
         INSERT INTO tblUpdate ;
            VALUES (ThisForm.txtValue.Value, RECCOUNT() + 1 )
      ENDPROC

      PROCEDURE cmdBrowse.Click
         BROWSE
      ENDPROC
   ENDDEFINE

2. Uncomment each UPDATE statement in turn to see the problem and the various
   workarounds.

Additional query words:

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Keywords          : kbDatabase kbSQL kbvfp300 kbvfp300b kbvfp500 kbvfp500a kbvfp600 KbDBFDBC kbGrpDSFox kbDSupport kbvfp700 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP500 kbVFP600 kbVFP700 kbVFP500a
Version           : :3.0,3.0b,5.0,5.0a,6.0,7.0
Issue type        : kbprb

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