Arithmetic expression in Open SQL. The operators perform arithmetic calculation between two adjacent operands. The possible operators are:
+ for adding the operands
- for subtracting the right operand from the left operand
* for multiplying the operands
/ for dividing the left operand by the right operand
The operators * and / have a higher priority than the operators + and -. Within a
parenthesis level, operations with a higher priority
are performed before those with a lower priority. Operations with identical priorities are performed
from left to right. A minus sign - can be placed in front of an operand that
does not directly follow an operator +, -, *, or /.
The arithmetic expressions in Open SQL are distinguished as follows, depending on the data type of the operands:
Integer Expressions
Integer expressions use only integer operators, regardless of the parenthesis level. These operators
have the dictionary type INT1, INT2, INT4, and INT8 or the ABAP type b,
s, i, and int8 plus packed numbers of the
types DEC, CURR, and QUAN or p without decimal places. The operator
/ is not allowed in integer expressions. An overflow occurs and an exception of the class CX_SY_OPEN_SQL_DB is raised when
the value range of the type INT4 or i is exceeded in operations between two integer numbers where neither of the numbers has the type INT8,
the value range of the type INT8 or int8 is exceeded in operations between two integer numbers where one of the numbers has the type INT8,
the value range of a packed number with length 31 without decimal places is exceeded in operations using packed numbers.
Depending on the types of the operators, the result has the type INT4, INT8 or (if packed numbers are involved) is a packed number number with length 31 and no decimal places. Using the associated
assignment rule, it can be assigned to all
numeric ABAP types whose value range is large enough, except for decimal floating point numbers.
Decimal Expressions
Alongside any integer operators (see above), decimal expression have at least one operator with the
type DEC, CURR, or QUAN or p with decimal places. The operator /
is not allowed in decimal expressions. The result has the type DEC with the length 31 and a maximum of 14 decimal places. Using the associated
assignment rule, it can be assigned to all
numeric ABAP types whose value range is large enough, except for decimal floating point numbers.
If a decimal expression is specified statically, the syntax check checks that the result of each operation
is in the value range of the type DEC with length 31 and a maximum of 14 decimal places. If any operands
are specified that could produce other values, a syntax error occurs. If the expression is specified dynamically, an exception of the class CX_SY_DYNAMIC_OSQL_SEMANTICS is raised in this case.
Floating Point Expressions
Floating point expressions only have operators with the dictionary type FLTP or with the ABAP type
f. Only floating point expressions permit division with the operator /.
If an operation exceeds the value range of the type FLTP or division by 0 takes place, an overflow occurs
and an exception of the class CX_SY_OPEN_SQL_DB is raised. The result has the type FLTP and can only be assigned to a field with the ABAP type f in accordance with the associated
assignment rule.
No other combinations of operand are allowed. The operands can be appropriate SQL expressions, which covers columns, literals, host variables, and host expressions.
If the operand of an arithmetic expression has the null value, the result of the full arithmetic expression is the null value.
Notes
The arithmetic expressions have been divided into the three categories integer expression, decimal expressions, and floating point expression to achieve the same behavior in all supported database systems.
Operators that do not have the type FLTP can be transformed to an operator with the type FLTP using
a CAST expression and hence used in floating point expressions.
A plus sign + cannot be specified in front of an operand of an arithmetic
expression. If a minus sign - is specified after an operator +,
-, *, or /, the sign and the operand must be placed in parentheses.
If an operand is prefixed with a minus sign (-), the syntax check is performed in a
strict mode, which handles the statement more strictly than the regular syntax check.