Is it possible to construct a full EAN 13 barcode string in a SQL SELECT query?

I am developing an Access "project" (.adp) as a front-end to a SQL Server database.

My client has his own EAN 13 barcode prefix and each stock item has its own unique number. I have been able to produce VBA code to pack put the stock number with leading zeroes, join it to the prefix and calculate the 13th checksum digit.

That all works OK for working within Access, but I am now using the SQL Server data as an ODBC source and would like to offer the full 13 digit barcode as a column from a new "View".

Can anyone suggest how I could create the full barcode in a SQL SELECT statement?

Many thanks. Colin.

colinasadAsked:
Who is Participating?
 
cyberkiwiConnect With a Mentor Commented:
Create the following function on SQL Server.
You can use this function in an expression, e.g.

select col1, col2, dbo.genBuildFullBarcode('MYPREFX', barcodenum, 1) as ean13barcode
from sometable
create Function dbo.genBuildFullBarcode
(@strPrefix varchar(50), @lngNumber int, @blnSeparate bit) returns varchar(50)
as
begin
    -- Build a full 13 digit barcode from a prefix and unique number - checksum digit is calculated
    
    -- strPrefix = Barcode prefix digits
    -- lngNumber = Item's unique number
    -- blnSeparate = Do we want to show gaps between main components ie ppppppp-nnnnn-c
    
    declare @intEvenTot int
    declare @intOddTot int
    declare @intCounter int
    declare @strBarcode varchar(50)
    
    set @intEvenTot = 0
    set @intOddTot = 0
    set @strBarcode = ''
    
    -- Pack out the unique number with leading zeroes and make it 5 digits long
    set @strBarcode = right('00000' + convert(varchar(50), @lngNumber), 5)
    
    -- Concatenate the unique number to the prefix (make sure it is 7 digits long, left pad with 0)
    set @strPrefix = right('0000000' + @strPrefix, 7)
    set @strBarcode = @strPrefix + @strBarcode
    
    -- Now calculate the 13th checksum digit
    If Len(@strBarcode) = 12
    begin
		set @intCounter = 1
		while @intCounter <= 12
		begin
            If (@intCounter % 2) = 0
                set @intEvenTot = @intEvenTot + ascii(substring(@strBarcode, @intCounter, 1)) - ascii('0')
            Else
                set @intOddTot = @intOddTot + ascii(substring(@strBarcode, @intCounter, 1)) - ascii('0')
            set @intCounter = @intCounter + 1
        end
                                        
        set @intEvenTot = (@intEvenTot * 3) + @intOddTot
        set @intEvenTot = (@intEvenTot % 10)
        if @intEvenTot > 0
            set @intEvenTot = 10 - @intEvenTot
        
        -- add checksum
        set @strBarcode = @strBarcode + convert(varchar(10),@intEvenTot)

        if @blnSeparate = 1
            -- Add a separator char to show how string is composed
            set @strBarcode = left(@strBarcode,7) + '-' + substring(@strBarcode, 8, 5) + '-' + right(@strBarcode, 1)
    end
    
    return @strBarcode
end
GO

Open in new window

0
 
cyberkiwiCommented:
We could translate the VBA code to make sure it is doing the same things?
Need the VBA code though.
0
 
tncodeCommented:
You may want to try this VBA encoder; it contains the ability to encode EAN barcodes. Though you must also use a barcode font.

http://www.idautomation.com/fonts/tools/vba/

Hope this helps.
0
Upgrade your Question Security!

Your question, your audience. Choose who sees your identity—and your question—with question security.

 
colinasadAuthor Commented:
Hello again, cyberkiwi. Thanks for the prompt response.

I have attached my VBA procedure for building a full 13 character barcode string.
I wouldn't know how to start to do this with SQL. I would be able to construct the first 12 digits OK but wouldn't know how to do the checksum calculation.

Regards. Colin.
Public Function genBuildFullBarcode(strPrefix As String, lngNumber As Long, blnSeparate As Boolean) As String
    ' Build a full 13 digit barcode from a prefix and unique number - checksum digit is calculated
    
    ' strPrefix = Barcode prefix digits
    ' lngNumber = Item's unique number
    ' blnSeparate = Do we want to show gaps between main components ie ppppppp-nnnnn-c
    
    Dim intEvenTot As Integer
    Dim intOddTot As Integer
    Dim intCounter As Integer
    Dim strBarcode As String
    
    intEvenTot = 0
    intOddTot = 0
    strBarcode = ""
    
    ' Pack out the unique number with leading zeroes and make it 5 digits long
    strBarcode = Trim(Str(lngNumber))
    strBarcode = Right("00000" & strBarcode, 5)
    
    ' Concatenate the unique number to the prefix (already 7 digits long)
    strBarcode = strPrefix & strBarcode
    
    ' Now calculate the 13th checksum digit
    If Len(strBarcode) = 12 Then
        For intCounter = 1 To 12
            If (intCounter Mod 2) = 0 Then
                intEvenTot = intEvenTot + Asc(Mid(strBarcode, intCounter, 1)) - Asc("0")
            Else
                intOddTot = intOddTot + Asc(Mid(strBarcode, intCounter, 1)) - Asc("0")
            End If
        Next intCounter
                                        
        intEvenTot = (intEvenTot * 3) + intOddTot
        intEvenTot = (intEvenTot Mod 10)
        If intEvenTot > 0 Then
            intEvenTot = 10 - intEvenTot
        End If
        
        
        If blnSeparate Then
            ' Add a separator char to show how string is composed
            strBarcode = Trim(Str(lngNumber))
            strBarcode = Right("00000" & strBarcode, 5)
            strBarcode = strPrefix & "-" & strBarcode & "-" & Trim(Str(intEvenTot))
        Else
            strBarcode = strBarcode & Trim(Str(intEvenTot))
        End If
    End If
    
    genBuildFullBarcode = strBarcode
End Function ' genBuildFullBarcode

Open in new window

0
 
colinasadAuthor Commented:
Many thanks, cyberkiwi, that worked fine.
I'm ashamed to say that I have not created any SQL Functions before. Because my application is in Access, nearly all of my programming is done in VBA and I have limited by SQL input to Views and Stored Procedures.
You have opened a new door for me.

Just before I award the well-earned points, can I ask if you painstakingly edited my VBA code by hand (replacing the comment prefix characters, changing "dim" to "declare", adding in "set" etc.) or is there a "VBA to SQL" convertor that does most of this?

Many thanks. Colin.
0
 
cyberkiwiCommented:
By hand, sir! :)
It was a hack job line for line.
If you expressed just the requirements, you may see a different approach, but I think this will do.

Have a good day.
Regards
0
 
colinasadAuthor Commented:
Many thanks, cyberkiwi
Your conversion of my Access VBA procedure to a SQL Server SQL function worked a treat.
0
All Courses

From novice to tech pro — start learning today.