CA 2E Quick Tour › Defining Functions › Default Reference File Functions

Default Reference File Functions

CA 2E automatically creates five default functions for each reference file (REF) you declare: two external functions (Edit File and Select Record), and three internal functions (Change Object, Create Object, and Delete Object).

The two external functions CA 2E automatically creates are:

• Edit File (EDTFIL)—this type of function maintains multiple records on the file.
• Select Record (SELRCD)—this type of function provides a display of the records on the file, and allows the selection of one record for return to a calling program.

Both of these external functions are interactive device functions.

The three internal functions CA 2E automatically creates are:

• Change Object (CHGOBJ)
• Create Object (CRTOBJ)
• Delete Object (DLTOBJ)

These functions are used to update the database and are called by external functions as required. They are implemented as subroutines within the generated source code for an external function. Internal functions are specified separately to give you the capability to add additional processing for updating the database. This additional processing is made available to all the functions that call the internal functions.

The five default functions for a file are created the first time you enter F against the file on the Edit Database Relations panel. For example, to create the default functions for the COURSE file you would do the following:

First, display just those relations defined for the COURSE file by entering Course* on the selection line of the Edit Database Relations panel.

Next, display the functions for a particular file by typing F against the file on the Edit Database Relations panel. Enter F next to any COURSE file relation as shown in the following example:

If you press Enter you can view the five default functions for the COURSE file.CA 2E displays messages at the bottom of the panel to indicate this as shown in the following example:

EDIT FUNCTIONS                           My model                            

 File name. . . : Course                                 **   1ST LEVEL  **  

 ? Function                    Function type             Access path            

   Change Course               Change object             Update index           

   Create Course               Create object             Update index           

   Delete Course               Delete object             Update index           

   Edit Course                 Edit file                 Retrieval index        

   Select Course               Select record             Retrieval index        

                                                                        More...

 SEL: Z=Details   P=Parms   F=Action diagram   S=Device   D=Delete   O=Open    

      T=Structure   A=Access path   G/J=Generate function   H=Generate HTML ...

 F3=Exit   F5=Reload   F7=File details   F9=Add functions   F23=More options   

 F11=Next View   F17=Services   F21=Copy *Template function