How Can This Produce An Error?

I have 2 comboboxes to select a product no, and a unit of measurement

I have a materialprices table with unique records, keyed on productno and unitno, so i should get either one or no records returned from the following SQL

However, if i compare the values of the returned records with the search values and the tests, it shows a difference, although the difference is then showing as zero when I evaluate it.

(I found this because initially I had written the code using seek, and was trying to ensure I had located the correct record)

I have actually got round this by testing the abs difference as being greater than a minuscule value.

ie
If abs(rs!pmpprodno - cboProd)>0.01 Or abs(rs!pmpunit - cboUnit)>0.01 which does not produce an error

I could understand this if I was testing real numbers, but these are all integers - any ideas anyone?


so ignoring the dims - ignore any typos - the code compiles and executes properly - its just the equality test thats the problem


function lookupmat as boolean

strsql = "select * from tblmatprices where [pmpprodno] = " & cboProd & _
" and [pmpunit] = " & cboUnit

Set rs = CurrentDb.OpenRecordset(strsql)

If rs.eof Then
lookupmat = False
rs.Close
GoTo exitproc
End If

'having used the above where clause to find an item, this test now seems to produce a difference, even though the figures are the same!
If rs!pmpprodno <> cboProd Or rs!pmpunit <> cboUnit Then MsgBox ("Unexpected - There is a difference " & vbCrLf & _
"cboProd = " & Format(cboProd, "###.0000000000") & _
" Lookup = " & Format(rs!pmpprodno, "###.0000000000") & vbCrLf & _
"cboUnit = " & Format(cboUnit, "###.0000000000") & _
" Lookup = " & Format(rs!pmpunit, "###.0000000000") & vbCrLf)

'and now both of these tests are showing a difference! of zero
If cboProd <> rs!pmpprodno Then MsgBox ("Prod Was different " & cboProd - rs!pmpprodno)
If cboUnit <> rs!pmpunit Then MsgBox ("Unit Was different " & cboUnit - rs!pmpunit)

lookupmat = False
rs.Close
GoTo exitproc
End If