2.22 Fields: Bar Codes

2.22.1 Field 1 Function Keys

2.22.2 Field 2 General Bar Code Format: 50 characters, tab stop

Purpose: To specify the bar code format that covers all possible uses.

Format: It uses a combination of "@" for Alpha, "#" for number, "&" for either alpha or numeric, and spaces that the bar code is expected to be in. All other characters are interpreted literally, including numbers. Leading zeros may be included literally as "0" or symbolically as #. The software does not perform any check digit processing on the bar code. Distinct patterns may be separated by an " OR ", minus the quotes.

Brief Examples:

Given a bar code of D12345, the pattern may be D##### or D1####. Given bar codes of D12345 and A54321, the pattern would be @#####. Given bar codes of D12345 and A1A123, the pattern would be @#&###, or the pattern could be "D1#### OR @#@###" but without the quotes.

2.22.3 Field 3 Bar Code Type: 20 characters

Purpose: To specify the Bar Code type.

Format: Entry should be a description of this bar code type.

Discussion: The bar code description should describe each unique bar code type. For example, bar code formats may be different for items such as books, audiovisuals, etc. If patrons also each have a unique bar code, it is usually a different format than the bar code format for items.

2.22.4 Field 4 Media Type Key: 1 character

Purpose: To specify the Media Type Key.

Format: It is a table selection of a unique one character Media Type Key.

Discussion: Each bar code type should have a unique one character key. For example, Patron bar codes could have a media key of 'P' while a Book bar code could have a media key of 'B'.

2.22.5 Field 5 Bar Code Format: 50 characters, tab stop

Purpose: To specify the bar code format that covers all possible uses.

Brief Examples:

Discussion: Bar code formats may come in many different formats. The "@" character may be used to indicate that any alpha character is permissible. The "#" character indicates that any number is a valid entry. The "&" character indicates either a number or an alpha character. If all bar codes should begin with a particular character, that character should be used in the pattern.

Examples:

             @@@ ####     3 Alpha characters followed by a space 
                          and then 4 numbers, e.g., ABC 1234 
  
             @## ####     1 Alpha character followed by 2 numbers, 
                          followed by a space and then 4 numbers, 
                          e.g., Z22 4444.  
  
             D##@@@@      Bar Code begins with a 'D', then two 
                          numbers and finally 4 alpha characters, 
                          e.g., D12QWER.  
  
  
             D##@@@&      Bar Code begins with a 'D', then two 
                          numbers, 3 alpha characters, and 
                          a final number or letter, e.g., 
                          D12ABCD or D34EFG7.

Format Journals is only used by old Georgetown University installations.

Important Note: The Circulation functions are designed to be "hands free", i.e., the Circulation desk user scans the patron's card, and then scans a book's bar code, and never touches the keyboard during this speedy transaction.

The software can do this only if the bar codes do not look like a patron number, MARC number, item number, etc.

Therefore, in the Circulation windows, when you are focused on a look up field which might accept a bar code (e.g., Patron Look Up or item Find) and scan a bar code, the software immediately tests the value to see if it looks like bar code by seeing if the value matches the bar code pattern. The value looks like a bar code, the user does not have to press the [Bar Code] push button, because the software will automatically process the value as a bar code, saving the user a motion and some time. The library application runs fast!

Again, the software really doesn't know that a reader (and not the keyboard) sent the characters. The way that the software tell is by the pattern. Here's the problem: the software can't tell that 10000 is a bar code or an item number or a MARC number. 10000 is just a number, could be a number for anything. It's important that the bar code have a unique pattern. The best any to do that is to have a non-numeric character in the pattern, for example:

            
     I10000

Therefore, when the software sees I##### it knows it is a bar code and nothing else, so it does not have to confirm with the user as to the meaning of I10000. The software simply graps the associated record.

You actually can use an all numeric bar code if the number of digits is very large. For example, if you will never have more than a 1,000,000 items or patrons, then you could have a bar code of 8 digits, and there would be no confusion in the software. 1 to 999999 would be item or patron numbers, and 00000001 to 99999999 would be bar codes to patrons or items.

Lastly, keep things simply. Make all of the bar code patterns the same, e.g.,

     Format     Pattern 
     -------    --------
     General    B####### 
     Item       B####### 
     Journal    B####### 
     Patron     B#######

The above patterns allow you to use interchangeable bar codes, which should make life easier. If you really want to have variety, then this would work too:

  
     Format     Pattern 
     -------    --------
     General    @####### 
     Item       I####### 
     Journal    J####### 
     Patron     P#######

Please avoid anything more extravagant. Bar codes are often the source of service calls.

2.22.6 Field 6 Controls Ok, Cancel, & Help: tab stop

Purpose: To specify an action that controls the window's flow. [Ok] will save and apply the displayed values, whereas [Cancel] will reject the changes. [Help] will display all of the documentation for the window. Press the Help key for context sensitive help for each field.

Format: It is an action that toggles the push button.

Menu Style: Push Button

Menu Values:
Ok
Cancel
Help