Teodor Macicas <teodor.macicas@epfl.ch> writes:
> Tom Lane wrote:
>> C code will work with a value in a "native" representation, and then
>> convert to or from Datum in order to pass the value through
>> data-type-independent interfaces.
> And how this convertions will be made ?
> Are there internal functions to do this ?
Usually you should use the appropriate DatumGetXXX or XXXGetDatum
macro, or possibly the PG_GET_XXX or PG_RETURN_XXX wrappers for those.
Whether that's a simple cast or a function call is the macro's business.
regards, tom lane