HOWTO: Extract Information from Excel Sheet with DAO

ID: Q190195

The information in this article applies to:

Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 6.0
Microsoft Visual Basic Professional and Enterprise Editions for Windows, version 5.0
The DAO SDK

SUMMARY

The Excel ISAM driver is limited in the sense that it does not dynamically convert datatypes.

MORE INFORMATION

If there is a column in your Excel spreadsheet that contains both text and numbers, the ISAM will not be able to correctly interpret which datatype it should be. Please make sure that all the cells in a column are formatted to be the same datatype. For example, you might have following data in four columns in an Excel sheet:


   male   female children teens
   11     cc     78       ee
   22     xx     33       ff
   45     uu     56       oo

If you try to read the data through ISAM driver against the whole sheet, you will get the null values for first row. If you want to avoid this, create named ranges; one containing only the header information and another one containing the data information, such as:


   named range 'myRange1' :
   male     female    children     teens

   named range 'myRange2' :
   11   cc   78   ee
   22   xx   33   ff
   45   uu   56   oo

Now you can connect to Excel and request information only from the particular named range. However, in one range, one particular column can contain only one type of data.

Creating a Range

Highlight the data. From the menu, select Insert->Name->Define->rangename. Note that the "refers to" box below will refer to your highlighted range; this should grow and shrink as data is inserted and deleted. To retrieve your data, use the range name you just created for the table name in your select statement.

Excel Steps

Create the Excel file, test.XLS, with following data in sheet1:


   excel File : test.xls with the following entries:

        male  female    children   teens
         11    cc       78           ee
         22    xx       33           ff
         45    uu       56           oo

Create the named range, myRange1 and myRange2, in the sheet containing the appropriate data.


      named range : myRange1

      male female children teens

      named range  : myRange2

      11     cc   78   ee
      22     xx   33   ff
      45     uu   56   oo

Visual Basic Steps

Create a new standard EXE project called "DAO_EXCEL."

Select References from the project menu and check Microsoft DAO 3.5 Library.

Place a CommandButton on the form.

Paste the following code in the form code window:


      private Sub Command_click1

      im dbtmp As DAO.Database
      im tblObj As DAO.TableDef
      im rs As DAO.Recordset

      et dbtmp = OpenDatabase_
           ("<complete path>\test.xls", False, True, "Excel 8.0;")

      DoEvents

      Set rs = dbtmp.OpenRecordset("select * from `myRange2`")
      While Not rs.EOF
          For x = 0 To rs.Fields.Count - 1
              Debug.Print rs.Fields(x).Value
          Next
          rs.MoveNext
      Wend
      End Sub

      Note the reverse apostrophe "`" while specifying the range
      name(myrange2).

The following results are as expected:


  11
  cc
  78
  ee
  22
  xx
  33
  ff
  45
  uu
  56
  oo

REFERENCES

Please refer to the documentation for how to connect to Excel through DAO. Another good reference will be the upcoming ADO->Excel reference.

Additional query words: kbDAO350 kbIISAM kbDatabase kbDSupport kbdse kbVBp500 kbVBp600

Keywords : kbGrpVBDB
Version : WINDOWS:5.0,6.0; winnt:
Platform : WINDOWS winnt
Issue type : kbhowto