Question

So, I’m building a simple inventory system. The information will be stored in a remote SQL Server 2005 database. On the current part of the project I’m working on I need to scan a barcode(which holds two pieces of data, employee ID and product ID). We’ll be using the MC9090-G scanner. At the same time it is being scanned, it will be sitting on a scale. I need to keep these three piece of data together, and upload them to the database.

First of all, I need to figure out how to collect the data. Secondly, I need to figure out the best platform to write the client side applications in. These will be fairly simple, such as inserting the above data. I’m not sure if I should use an ACCESS 2010 front end, or write the front end with something else.

I’m sorry if this question appears vague, please ask me for any more details. Thanks for the help guys, I’m really lost here.

Answer 1

This is a duplicate of your previous question. You don’t have to re-create a new question for it to be visible again: just edit your original question with more data and it will go to the top again.

No-one was able to answer then simply because this is too vague. For these types of systems, how the worker physically work is what drives the solution: you need to streamline their actions so that they flow naturally and do not require more movements and confirmations and handling than strictly necessary.

So, let’s try something.

Assumptions

Because I don’t know enough about your environment, equipment and process, I’ll make some assumptions about the problem:

• A computer is installed near the scale for data input.

• The barcode scanner and scale are both connected to the computer

• The barcode reader behaves like a HID device (like if the input was typed on a keyboard )

• The barcode reader is configured to add a CR (carriage return) suffix after each scan (all readers have this type of configuration).

• The employee barcode is printed along (above or below) the Product ID a label that is applied on the fish.
  The Employee ID barcode will be of the form: @123456 where 123456 is the employee ID.
  The @ prefix allows the system to detect that the scanned barcode is an Employee ID.
  Use Code128 or similar to print alphanumerical strings.

• The fish barcode label is assumed to be on the fish or printed on a card.
  The fish bar code label can be anything, but must not start with @.

• We assume that the scale has an interface. Since you don’t mention which one you use or how the data is retrieved from the PC, we’ll have to assume that there is a SDK provided with the scale, or something that allows you to read the current weight.
  Let’s call that function ReadScale() and assume it returns you a float with the weight in whatever measurement makes sense for your task.

Worker Process

Here again, we make some assumptions. Depending on your exact setup and what is the flow of actions physically performed, things may be very different, in which case, your software may also need to behave differently.

I assume that by the weighting and data entry is the final operation: the label is already applied on the fish/product by that time.

Possible process:

• The worker is on the front of the computer and scale

• The worker puts the fish on the scale

• The worker wait for the reading to stabilise

• The worker scans the 2 barcodes on the label placed on the fish.

Alternatively:

• The worker scans the 2 barcodes on the label placed on the fish.

• The worker puts the fish on the scale

• The worker wait for the reading to stabilise

• The worker types the ENTER key on the keyboard or scans a special OK barcode that tells the software that the process is completed.

The first alternative requires less operations, but it requires that the labels are visible for scanning while the product is on the scale. That may or may not be true.

Software solution

There are a thousand different ways to achieve what you want, but since you mentioned Access, we’ll assume that is what you are comfortable with.
Beside, it provides a nice way to prototype a solution since it’s easy to update an Access application.

I assume that the SQL Server database is on the same LAN as the data input computer that will host the Access application.
If that’s not the case, or if you must use Wifi, the way to connect to the database and save data would be different (and probably a bit more complex).

Data flow

When the employee scans the barcodes, the application will receive a stream of keys, as if the employee actually typed on the keyboard:

For instance, say the user scanned the employee ID, then the product ID. The computer will receive the following stream of data as if it was coming from the keyboard:

@443678¶
876657098¶

The ¶ symbol just represents the CR code suffix added by teh bar code scanner (same code as the ENTER key).

SQL Server Database

I assume that you have a ProductLog table in a Fishery database on SQL Server.
That ProductLog table will simply record the set of data for each fish/product:

ID          : Auto-increment ID (IDENTITY), to identify each record uniquely
EmployeeID  : Stores the Employee ID (INT/CHAR) 
ProductID   : stores the Product ID (INT/CHAR)
Weight      : Store the measured weight (FLOAT)
TimeStamp   : records the operation's exact date and time (DATETIME).

Now link the ProductLog table to your Access application front-end.
We’ll then be able to use it as if it was a local Access table.

Data input form

Le’t go for the most basic thing: create a blank form and add 3 large labels to it, that you will call: labelEmployeeID, labelProductID and labelWeight.

Edit the form’s properties so that it becomes modal and stays in the front of the application, among other things:

Default View    : Single Form
Record Selector : No
Pop up          : yes
Modal           : yes
key Preview     : Yes  (on the Events page)

Open the VBA IDE to edit the code for the form and add the following:

Option Compare Database
Option Explicit

' The SQL Server Connection String. Update to match your database '
Const SQLSERVERCONSTR As String = "ODBC;DRIVER=SQL Server;SERVER=MYSERVER;DATABASE=Fishery;Trusted_Connection=Yes;"

' Just clear the labels on the screen when we open the form '
Private Sub Form_Load()
    labelEmployeeID.Caption = "-"
    LabelProductID.Caption = "-"
    labelWeight.Caption = "-"
End Sub

' Most of the processing is done here: the barcode scanner will act   '
' as if the scanned code was typed on the keyboard.                   '
' We trap each keystroke and use a basic state machine to reconstruct '
' each barcode and process them once they have been received          '
Private Sub Form_KeyPress(KeyAscii As Integer)
    ' Status = 0 : Waiting for any barcode input        '
    ' Status = 1 : Currently reading EmployeeID barcode '
    ' Status = 2 : Currently reading ProductID barcode  '
    ' Status = 3 : All barcode data read                '
    Static Status As Integer
    ' Keep track of our barcodes '
    Static EmployeeID As String
    Static ProductID As String

    ' All barcodes entered, but not processed yet, do not accept more entry '
    If Status = 3 Then Exit Sub

    ' We received a CR, check if we have both barcodes and complete '
    If KeyAscii = vbKeyReturn Then
        Dim employeeCodeReceived As Boolean
        Dim productCodeReceived As Boolean
        employeeCodeReceived = (EmployeeID <> vbNullString)
        productCodeReceived = (ProductID <> vbNullString)

        ' Update UI to reflect the completed code we scanned '
        If employeeCodeReceived Then
            labelEmployeeID.Caption = "Employee : " & EmployeeID
        Else
            labelEmployeeID.Caption = "-"
        End If

        If productCodeReceived Then
            LabelProductID.Caption = "Product  : " & ProductID
        Else
            LabelProductID.Caption = "-"
        End If

        labelWeight.Caption = "-"

        ' If both have been received, complete the transaction '
        If employeeCodeReceived And productCodeReceived Then
            Status = 3
            ' Get the weight from the scales '
            Dim weight As Double
            weight = ReadScale()
            ' Display the weight '
            labelWeight.Caption = "Weight   : " & Format(weight, "0.000") & " kg"
            ' Save to log '
            Save EmployeeID, ProductID, weight
            ' Reset barcode data '
            EmployeeID = vbNullString
            ProductID = vbNullString
        End If
        Status = 0
        Exit Sub
    End If

    Dim c As String
    c = Chr(KeyAscii)

    ' We're starting a barcode '
    If Status = 0 Then
        If c = "@" Then
            Status = 1
            EmployeeID = vbNullString
            Exit Sub ' Skip the @ prefix '
        Else
            Status = 2
            ProductID = vbNullString
        End If
    End If

    If Status = 1 Then
        EmployeeID = EmployeeID & c
    ElseIf Status = 2 Then
        ProductID = ProductID & c
    End If
End Sub

Private Sub Save(ByVal EmployeeID As String, ByVal ProductID As String, ByVal weight As Double)
    ' We use ADO and late binding to avoid requiring a library reference '
    Dim rs As Object
    Set rs = CreateObject("ADODB.Recordset")

    ' Open using options adOpenDynamic(2) and adLockOptimistic(3) '
    rs.Open "ProductLog", SQLSERVERCONSTR, 2, 3
    ' Add a new record and close '
    With rs
        .AddNew
        !EmployeeID = EmployeeID
        !ProductID = ProductID
        !weight = weight
        !timestamp = Now()
        .Update
        .Close
    End With
    Set rs = Nothing

End Sub

' Magic function to be replaced by whatever you need to do to read the scale '
Private Function ReadScale() As Double
    Randomize
    ReadScale = Rnd() * 2
End Function

All this is of course a particularly simple implementation based on simple assumptions that may or may not match your particular case.
There is no error handling, and it’s not even very good code, but it can help you throw something together and get started.

Use

To try to simulate the data entry process, just open the form and use the keyboard.
For instance, entering the following (entering ProductID first then EmployeeID will also work):

@TIMOTHY¶
987654¶

Will result in this screen, with the data being automatically recorded:

Sample database

I’ve made public a sample database showing the code in action.
It will save the data to itself for the demo.
Download it.

Conclusion

Again, the main issue when building these warehouse data entry applications is to model the data entry to an actual streamlined physical process.
If you do not think about the actual environment and practices of the user, your solution may risk being counter-productive, requiring more effort for the worker and making his job awkward instead of efficient.