pub struct Nullable<T> { /* private fields */ }
Expand description
Wraps a type T together with an additional indicator. This way the type gains a Null representation, those memory layout is compatible with ODBC.
Implementations§
Trait Implementations§
source§impl<T> CData for Nullable<T>where
T: Pod,
impl<T> CData for Nullable<T>where
T: Pod,
source§fn cdata_type(&self) -> CDataType
fn cdata_type(&self) -> CDataType
The identifier of the C data type of the value buffer. When it is retrieving data from the
data source with
fetch
, the driver converts the data to this type. When it sends data to
the source, the driver converts the data from this type. Read moresource§fn indicator_ptr(&self) -> *const isize
fn indicator_ptr(&self) -> *const isize
Indicates the length of variable sized types. May be zero for fixed sized types. Used to
determine the size or existence of input parameters. Read more
source§fn value_ptr(&self) -> *const c_void
fn value_ptr(&self) -> *const c_void
Pointer to a value corresponding to the one described by
cdata_type
.source§fn buffer_length(&self) -> isize
fn buffer_length(&self) -> isize
Maximum length of the type in bytes (not characters). It is required to index values in
bound buffers, if more than one parameter is bound. Can be set to zero for types not bound
as parameter arrays, i.e.
CStr
. Read moresource§impl<T> CDataMut for Nullable<T>where
T: Pod,
impl<T> CDataMut for Nullable<T>where
T: Pod,
source§fn mut_indicator_ptr(&mut self) -> *mut isize
fn mut_indicator_ptr(&mut self) -> *mut isize
Indicates the length of variable sized types. May be zero for fixed sized types.
source§fn mut_value_ptr(&mut self) -> *mut c_void
fn mut_value_ptr(&mut self) -> *mut c_void
Pointer to a value corresponding to the one described by
cdata_type
.