OVRLAY: Overlaying a Character String

How to:

Available Languages: reporting

The OVRLAY function overlays a base character string with a substring. The function enables you to edit part of an alphanumeric field without replacing the entire field.

There is a version of the OVRLAY function that is available only in the Maintain language. For information on this function, see OVRLAY: Overlaying a Character String (Maintain).

Syntax: How to Overlay a Character String 

OVRLAY(source_string, length, substring, sublen, position, output)

where:

source_string

Alphanumeric

Is the base character string.

stringlen

Integer

Is the number of characters in source_string and output, or a field that contains the length. If this argument is less than or equal to 0, unpredictable results occur.

substring

Alphanumeric

Is the substring that will overlay source_string.

sublen

Integer

Is the number of characters in substring, or a field that contains the length. If this argument is less than or equal to 0, the function returns spaces.

position

Integer

Is the position in source_string at which the overlay begins. If this argument is less than or equal to 0, the function returns spaces. If this argument is larger than stringlen, the function returns the source string.

output

Alphanumeric

Is the name of the field that contains the result, or the format of the output value enclosed in single quotation marks. If the overlaid string is longer than the output field, the string is truncated to fit the field.

Note that if the overlaid string is longer than the output field, the string is truncated to fit the field.

Example: Replacing Characters in a Character String

OVRLAY replaces the last three characters of EMP_ID with CURR_JOBCODE to create a new security identification code and stores the result in NEW_ID: 

TABLE FILE EMPLOYEE
PRINT EMP_ID AND CURR_JOBCODE AND COMPUTE
NEW_ID/A9 = OVRLAY(EMP_ID, 9, CURR_JOBCODE, 3, 7, NEW_ID);
BY LAST_NAME BY FIRST_NAME
WHERE DEPARTMENT EQ 'MIS';
END

The output is: 

LAST_NAME        FIRST_NAME  EMP_ID     CURR_JOBCODE  NEW_ID
---------        ----------  ------     ------------  ------
BLACKWOOD        ROSEMARIE   326179357  B04           326179B04
CROSS            BARBARA     818692173  A17           818692A17
GREENSPAN        MARY        543729165  A07           543729A07
JONES            DIANE       117593129  B03           117593B03
MCCOY            JOHN        219984371  B02           219984B02
SMITH            MARY        112847612  B14           112847B14