Datatype conversions change an expression from one datatype to another and reformat date and time information. Adaptive Server provides three datatype conversion functions, convert, inttohex, and hextoint.
Adaptive Server performs certain datatype conversions automatically. These are called implicit conversions. For example, if you compare a char expression and a datetime expression, or a smallint expression and an int expression, or char expressions of different lengths, Adaptive Server automatically converts one datatype to another.
You must request other datatype conversions explicitly, using one of the built-in datatype conversion functions. For example, before concatenating numeric expressions, you must convert them to character expressions.
Adaptive Server does not allow you to convert certain datatypes to certain other datatypes, either implicitly or explicitly. For example, you cannot convert smallint data to datetime or datetime data to smallint. Unsupported conversions result in error messages.
