Search button using more than one text field Access vba - sql

Question

This is my code below. I am trying to search a database using two different dates, company name
I am getting an error when one of the date fields is empty or null. How can I solve this issue or bypass if the date search field is empty to ignore it in the search or search for an empty field?
Dim SQL As String
SQL = "SELECT * from qryRequestInternal where ([DateRequestSent] = #" & txt_Search_Sdate & "# AND [DateReceived] = #" & txt_Search_Rdate & "# AND (companyName like ""*" & txt_SCompNa & "*"") )"
Me.sfrmRequestInternal.Form.RecordSource = SQL
Me.sfrmRequestInternal.Form.Requery
Me.sfrmRequestInternal_col.Form.RecordSource = SQL
Me.sfrmRequestInternal_col.Form.Requery
End Sub

Answer 1

You will need to check for Null values and build the SQL string based on the controls which have a value (i.e. not null).
The example below uses a helper function to build the sql string. If nothing is inserted, it will only run the the Select * from qryRequestInternal without any criteria.
Private Function SqlWhere() As String
Dim retvalue As String
'sent date
With txt_Search_Sdate
If Not IsNull(.Value) Then
retvalue = " WHERE [DateRequestSent] = #" & Format(.Value, "mm/dd/yyyy") & "#"
End If
End With
'received date
With txt_Search_Rdate
If Not IsNull(.Value) Then
retvalue = IIf(Len(retvalue) = 0, " WHERE", retvalue & " AND") & " [DateReceived] = #" & Format(.Value, "mm/dd/yyyy") & "#"
End If
End With
'company
With txt_SCompNa
If Not IsNull(.Value) Then
retvalue = IIf(Len(retvalue) = 0, " WHERE", retvalue & " AND") & " [companyName] Like '*" & .Value & "*'"
End If
End With
SqlWhere = retvalue
End Function
To call it:
Dim sqlString As String
sqlString = "SELECT * from qryRequestInternal" & SqlWhere()
Debug.Print sqlString