Use the @STRNCAT function to concatenate one or more strings to a maximum length.
Syntax
result = @STRNCAT (string, max_length [, string, max_length, ...])
string-
Can be the name of a column or a literal string. Enclose literals within quotation marks.
max_length-
The maximum string length, in characters.
Example
The following concatenates two strings and results in "ABC123."
PHONE_NO = @STRNCAT ("ABCDEF", 3, "123", 3)