You can use subscripts with variables of CHAR, VARCHAR,
NCHAR, NVARCHAR, BYTE, or TEXT data type. The subscripts indicate
the starting and ending character positions that you want to use within
the variable.
Subscripts must always be constants. You cannot
use variables as subscripts. The following figure illustrates how
to use a subscript with a CHAR(15) variable. Figure 1: A subscript with a CHAR(15)
variable.
DEFINE name CHAR(15);
LET name[4,7] = 'Ream';
SELECT fname[1,3] INTO name[1,3] FROM customer
WHERE lname = 'Ream';
In this example, the customer's last name is placed between
positions 4 and 7 of name. The first three characters of the
customer's first name is retrieved into positions 1 through 3 of name.
The part of the variable that is delimited by the two subscripts is
referred to as a substring.