SUBTO

SUBTO returns a substring, specified by y and z, of x.

Read syntax diagramSkip visual syntax diagramSUBTO( x, y, z)
x
String expression. It specifies the string from which the substring is extracted. If x is not a string, it is converted to character.
y
Expression that is converted to FIXED BINARY(31,0). y specifies the starting position of the substring in x.
z
Expression that is converted to FIXED BINARY(31,0). z specifies the ending position of the substring in x. If z = y-1, a null string is returned. If z is omitted, the substring returned is position y in x to the end of x.

SUBTO(x,y) is equivalent to SUBSTR(x,y), and SUBTO(x,y,z) is equivalent to SUBSTR(x,y,z-y+1).

The STRINGRANGE condition is raised for a SUBTO reference if and only if the STRINGRANGE condition would be raised for the equivalent SUBSTR reference. In particular, this means that if k = length(x), then STRINGRANGE would be raised for SUBTO(x,y,z) under any of these 5 conditions:
 
         y < 1
         y > k+1
         y = k+1 then unless z = k
         z-y+1 < 0
         z > k