KB198504 - ACC2000: "Too Many Fields Defined" Error Message Saving Table

Article ID: 198504

Article Last Modified on 6/23/2005

Microsoft Access 2000 Standard Edition

This article was previously published under Q198504

Moderate: Requires basic macro, coding, and interoperability skills.

This article applies only to a Microsoft Access database (.mdb).

For a Microsoft Access 2002 version of this article, see 291556.

SYMPTOMS

When you save a table after you add a new field or change the properties of an existing field, you receive the message:

Too many fields defined.

This message is followed by:

Errors were encountered during save. Data types were not changed.

You receive these messages even though you have 255 or fewer fields defined in the table.

NOTE: You also receive this message if you add or modify fields in a report that is based on a table that has too many fields.

CAUSE

The internal column count that Microsoft Access uses to track the number of fields in the table has reached 255, even though you may have fewer than 255 fields in the table. This can happen because Access does not change the internal column count when you delete a field. Access also creates a new field (increasing the internal column count by 1) for every field whose properties you modify.

RESOLUTION

To free the internal column count for deleted fields or for fields whose properties you modify, do one of the following:

Compact the database. On the Tools menu, point to Database Utilities, and then click Compact and Repair Database.
-or-
Create a new copy of the table. To do so, follow these steps:

Make note of any relationships with the table.
Select the table.
On the File menu, click Save As.
In the Save Table 'table name' To box, type a new name. Click OK.
Select the same table that you selected in step 2, and then press DELETE.
Rename the table that you saved in step 3 to the original table name.
Re-establish any relationships with the new table.

MORE INFORMATION

Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements. NOTE: The sample code in this article uses Microsoft Data Access Objects. For this code to run properly, you must reference the Microsoft DAO 3.6 Object Library. To do so, click References on the Tools menu in the Visual Basic Editor, and make sure that the Microsoft DAO 3.6 Object Library check box is selected.

In Access, you can define up to 255 fields in a table. If you create 255 fields and then delete 10, Access does not release the fields from the internal column count. Also, for every field whose properties you modify, Access creates a new field and does not release the original field from the internal column count.

Steps to Reproduce Behavior

Create the following Visual Basic for Applications code to create a new table with 255 fields:

' ****************************************************************
' Declarations section of the module
' ****************************************************************

Option Compare Database
Option Explicit

' ****************************************************************
' The Fill_Table() function creates a table in the current database
' named Field Test with 255 fields, each of which has a Text data
' type and a size of one character.
' ****************************************************************

Function Fill_Table()
      
   Dim mydb As DAO.Database
   Dim tbl As DAO.TableDef
   Dim fld As DAO.Field
   Dim i As Integer
      
   Set mydb = CurrentDb()
   Set tbl = mydb.CreateTableDef("Field Test")
      For i = 0 To 254
         Set fld = tbl.CreateField("Field" & CStr(i + 1))
         fld.Type = dbText
         fld.Size = 1
         tbl.Fields.Append fld
      Next i
      mydb.TableDefs.Append tbl

End Function

Type the following line in the Immediate window to run the function and create the table:
```
Fill_Table
					
```
View the Field Test table in Design view, and delete the last field so that there are only 254 fields defined in the table.
Add the field again, and try to save the table. You see the following error messages:
Too many fields defined.

Errors were encountered during the save operation. Fields were not added. Properties were not updated.

REFERENCES

For more information about database specifications, click Microsoft Access Help on the Help menu, type Microsoft Access specifications in the Office Assistant or the Answer Wizard, and then click Search to view the topics returned.

Additional query words: prb

Keywords: kberrmsg kbprb KB198504