ABAP Keyword Documentation →  ABAP - Reference →  Program Flow Logic →  Expressions and Functions for Conditions →  log_exp - Logical Expressions →  rel_exp - Comparison Expressions →  rel_exp - Comparison Rules →  rel_exp - Comparing Elementary Data Types →  rel_exp - Comparison Type of Elementary Data Objects 

rel_exp - Comparison Type of Byte-Like Data Objects

The following tables show the comparison types for comparisons between byte-like data types and other data types. If the type of an operand is not the same as the comparison type, then it is converted to this type. The comparison rules for the comparison types determine how the comparison is performed.

• Comparisons with Numeric Data Types

• Comparisons with Character-Like Data Types

• Comparisons with Byte-Like Data Types

Other versions: 7.31 | 7.40 | 7.54

Comparisons with Numeric Data Types

-	xstring, x
decfloat34	decfloat34
decfloat16	decfloat34
f	f
p	p
i, s, b	i

Length Adjustments

The comparison type p has 31 decimal places and the number of places in the decimal portion in the operand of type p.

Note

When converting byte-like data types to numeric types, note that all bytes are ignored except for the final four.

Comparisons with Character-Like Data Types

-	xstring	x
string	string	string
c	string	c
n	p	p
d,t	i	i

Length Adjustments

• When data type c is compared with x or xstring, the shorter field is adjusted to the length of the longer field after conversions from x to c or xstring to string. Blanks are used as filler on the right.

• Lengths are not adjusted for comparisons between the data type string and x or xstring.

Comparisons with Byte-Like Data Types

-	xstring	x
xstring	xstring	xstring
x	xstring	x

Length Adjustments

• Operands of data type xstring with different lengths never match. If the contents of the operands match across the length of the shorter operand, the shorter operand is smaller than the longer one. Otherwise the surplus bytes in the longer field are truncated on the right, and then the content is compared.

• For comparisons between two operands of data type c, the shorter field is converted to the longer field, with hexadecimal 0 used as filler on the right.

Example

The first comparison uses the appropriate conversion rules to convert the hexadecimal content "FF00" of hex to the string "FF00"; this string is then compared with "FFxx". Before the second comparison, the appropriate conversion rules are used to convert the content of text to the hexadecimal value "FF00" in the helper variable hex_helper and this value is compared with the content of hex.

DATA hex        TYPE x LENGTH 2. 
DATA text       TYPE c LENGTH 4. 
DATA hex_helper TYPE x LENGTH 2. 

hex  = 'FF00'. 
text = 'FFxx'. 

IF hex <> text. 
  cl_demo_output=>write_text( |{ hex } <> { text } | ). 
ENDIF. 

hex_helper = text. 
IF hex = hex_helper. 
  cl_demo_output=>write_text( |{ hex } = { hex_helper } | ). 
ENDIF. 

cl_demo_output=>display( ).