Raise exception when the user entered value is not present

Question

Hello Abap experts,
To raise an exception in the function module when the imported variable value is not presnt in the table.
import variable: cust_name.
how to define a exception for this raise it in the code. any examples and suggestions.
Thanks,
BWer

Answer 1

Here is the F1 help on RAISE.
<i>
RAISE
Basic form 1
RAISE except.
Effect
This statement is only effective in function modules and methods.
It triggers the exception except.
If the exception is to be handled by the caller of the function module or method ( CALL FUNCTION or CALL METHOD ), the system passes control straight back to the caller. EXPORT parameters of a function module or method are not filled. The EXPORTING, CHANGING, and RETURNING parameters of a function module or method are only filled with the current values if they were defined to be passed by reference. reference).If they are defined to be passed by value, they are not filled.
If the exception is not handled by the caller, the program terminates with an appropriate error message.
Example
Let there be a function module STRING_SPLIT containing the following code (see also the example in the documentation of the CALL FUNCTION statement):</i>
<b>FUNCTION-POOL CSTR.
FUNCTION STRING_SPLIT.
  IF STRING NA DELIMITER.
    RAISE NOT_FOUND.
  ENDIF.
ENDFUNCTION.</b>
The calling program might then contain the following:
<b>PROGRAM EXAMPLE.
CALL FUNCTION 'STRING_SPLIT'
     EXCEPTIONS
          NOT_FOUND = 7.
IF SY-SUBRC = 7.
  WRITE / 'There is a problem.'.
ELSE.
ENDIF.</b>
<i>
If the NOT_FOUND exception is raised in a RAISE statement in the function module STRING_SPLIT, the system exits the function module and returns control to the calling program. The return code, which you should evaluate directly after the CALL FUNCTION statement, now contains the value 7.
Note
Runtime errors:
RAISE_EXCEPTION: The caller did not handle the exception that was triggered.
Related
MESSAGE ... RAISING
Additional help
Creating Function Modules
</i>
Regards,
Rich Heilman