pgx::htup

Function heap_getattr

Source 
pub fn heap_getattr<T: FromDatum, AllocatedBy: WhoAllocated>(
    tuple: &PgBox<HeapTupleData, AllocatedBy>,
    attno: NonZeroUsize,
    tupdesc: &PgTupleDesc<'_>,
) -> Option<T>
Expand description

Extract an attribute of a heap tuple and return it as Rust type. This works for either system or user attributes. The given attnum is properly range-checked.

If the field in question has a NULL value, we return None. Otherwise, a Some(T)

‘tup’ is the pointer to the heap tuple. ‘attnum’ is the attribute number of the column (field) caller wants. ‘tupleDesc’ is a pointer to the structure describing the row and all its fields.

attno is 1-based