SAP LOGEXP RULES OPERANDS DOBJ

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rel_exp - Comparisons of Elementary Data Objects
The following sections describe which comparison types result from combining different data objects. They also include the rules that determine the length in which the comparison is made when comparison types have generic lengths.

Comparing Numeric Data Types

Comparing Character-Like Data Types

Comparing Byte-Like Data Types

Note
When converting between elementary data objects with different data types, any of the exceptions listed here can be raised. In comparisons, these exceptions can never be handled and always produce a runtime error.