Struct SQLHDESC 

pub struct SQLHDESC<'conn, DT, V: OdbcVersion = SQL_OV_ODBC3_80>(/* private fields */);

A descriptor is a collection of metadata that describes the parameters of an SQL statement or the columns of a result set. Thus, a descriptor can fill four roles:

• (APD)Application Parameter Descriptor: Contains information about the application buffers bound to the parameters in an SQL statement, such as their addresses, lengths, and C data types.
• (IPD)Implementation Parameter Descriptor: Contains information about the parameters in an SQL statement, such as their SQL data types, lengths, and nullability.
• (ARD)Application Row Descriptor: Contains information about the application buffers bound to the columns in a result set, such as their addresses, lengths, and C data types.
• (IRD)Implementation Row Descriptor: Contains information about the columns in a result set, such as their SQL data types, lengths, and nullability.

Four descriptors are allocated automatically when a statement is allocated, but applications can also allocate descriptors with SQLAllocHandle. They are allocated on a connection and can be associated with one or more statements on that connection to fulfill the role of an APD or ARD on those statements.

Documentation

https://docs.microsoft.com/en-us/sql/odbc/reference/develop-app/descriptor-handles

Trait Implementations

impl<'env, 'conn, 'buf, V: OdbcVersion> Allocate<'conn, SQLHDBC<'env, C4, V>> for SQLHDESC<'conn, AppDesc<'buf>, V>

unsafe fn from_raw(handle: NonNull<RawHandle>) -> Self

Creates handle from a raw pointer

fn SQLAllocHandle(InputHandle: &'src SRC) -> (Result<Self, ()>, SQLRETURN)

Allocates an environment, connection, statement, or descriptor handle.

fn SQLFreeHandle(self)

Frees resources associated with a specific environment, connection, statement, or descriptor handle.

impl<V: OdbcVersion, T> AsSQLHANDLE for SQLHDESC<'_, T, V>

fn as_SQLHANDLE(&self) -> SQLHANDLE

impl<'conn, DT: Debug, V: Debug + OdbcVersion> Debug for SQLHDESC<'conn, DT, V>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, T> DescField<'buf, SQLHDESC<'conn, DT>, DT, A, SQL_OV_ODBC3_80> for T

where T: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion> + Scalar,

fn update_handle(&self, _: &D)

where Self: AttrSet<A>,

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, T> DescField<'buf, SQLHDESC<'conn, DT, SQL_OV_ODBC4>, DT, A, SQL_OV_ODBC4> for T

where T: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion> + Scalar,

fn update_handle(&self, _: &D)

where Self: AttrSet<A>,

impl<'conn, 'buf, DT: DescType<'buf>, V: OdbcVersion> Descriptor<'buf, DT, V> for SQLHDESC<'conn, DT, V>

fn SQLCopyDesc<DT2: DescType<'buf>>( &self, TargetDescHandle: &SQLHDESC<'_, DT2, V>, ) -> SQLRETURN

Copies descriptor information from one descriptor handle to another.

fn SQLGetDescFieldA<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: SQLSMALLINT, FieldIdentifier: A, ValuePtr: Option<&mut T>, StringLengthPtr: Option<&mut MaybeUninit<T::StrLen>>, ) -> SQLRETURN

where T: AttrGet<A> + Ansi + ?Sized + DescField<'buf, Self, DT, A, V>, MaybeUninit<T::StrLen>: StrLen<SQLINTEGER>,

Returns the current setting or value of a single field of a descriptor record.

fn SQLGetDescFieldW<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: SQLSMALLINT, FieldIdentifier: A, ValuePtr: Option<&mut T>, StringLengthPtr: Option<&mut MaybeUninit<T::StrLen>>, ) -> SQLRETURN

where T: AttrGet<A> + Unicode + ?Sized + DescField<'buf, Self, DT, A, V>, MaybeUninit<T::StrLen>: StrLen<SQLINTEGER>,

Returns the current setting or value of a single field of a descriptor record.

fn SQLGetDescRecA<ST: SqlType<V>>( &self, RecNumber: SQLSMALLINT, Name: Option<&mut OdbcStr<MaybeUninit<SQLCHAR>>>, StringLengthPtr: &mut impl AsMutPtr<SQLSMALLINT>, TypePtr: &mut impl AsMutPtr<ST>, SubTypePtr: &mut impl AsMutPtr<DatetimeIntervalCode>, LengthPtr: &mut impl AsMutPtr<SQLLEN>, PrecisionPtr: &mut impl AsMutPtr<SQLSMALLINT>, ScalePtr: &mut impl AsMutPtr<SQLSMALLINT>, NullablePtr: &mut impl AsMutPtr<NullAllowed>, ) -> SQLRETURN

Returns the current settings or values of multiple fields of a descriptor record. The fields returned describe the name, data type, and storage of column or parameter data.

fn SQLGetDescRecW<ST: SqlType<V>>( &self, RecNumber: SQLSMALLINT, Name: Option<&mut OdbcStr<MaybeUninit<SQLWCHAR>>>, StringLengthPtr: &mut impl AsMutPtr<SQLSMALLINT>, TypePtr: &mut impl AsMutPtr<ST>, SubTypePtr: &mut impl AsMutPtr<DatetimeIntervalCode>, LengthPtr: &mut impl AsMutPtr<SQLLEN>, PrecisionPtr: &mut impl AsMutPtr<SQLSMALLINT>, ScalePtr: &mut impl AsMutPtr<SQLSMALLINT>, NullablePtr: &mut impl AsMutPtr<NullAllowed>, ) -> SQLRETURN

Returns the current settings or values of multiple fields of a descriptor record. The fields returned describe the name, data type, and storage of column or parameter data.

fn SQLSetDescFieldA<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: SQLSMALLINT, FieldIdentifier: A, ValuePtr: Option<T>, ) -> SQLRETURN

where T: AttrSet<A> + Ansi + DescField<'buf, Self, DT, A, V>,

Sets the value of a single field of a descriptor record.

fn SQLSetDescFieldW<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: SQLSMALLINT, FieldIdentifier: A, ValuePtr: Option<T>, ) -> SQLRETURN

where T: AttrSet<A> + Unicode + DescField<'buf, Self, DT, A, V>,

Sets the value of a single field of a descriptor record.

fn SQLSetDescRec<ST: SqlType<V>, PTR>( &self, RecNumber: SQLSMALLINT, Type: ST, SubType: Option<DatetimeIntervalCode>, Length: SQLLEN, Precision: SQLSMALLINT, Scale: SQLSMALLINT, DataPtr: Option<&'buf PTR>, StringLengthPtr: &'buf mut impl AsMutPtr<SQLLEN>, IndicatorPtr: &'buf mut impl AsMutPtr<SQLLEN>, ) -> SQLRETURN

where &'buf PTR: IntoSQLPOINTER,

Sets multiple descriptor fields that affect the data type and buffer bound to a column or parameter data.

impl<DT, V: OdbcVersion> Diagnostics for SQLHDESC<'_, DT, V>

fn SQLGetDiagFieldA<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: NonZeroI16, DiagIdentifier: A, DiagInfoPtr: Option<&mut T>, StringLengthPtr: Option<&mut MaybeUninit<T::StrLen>>, ) -> SQLRETURN

where T: AttrGet<A> + Ansi + ?Sized + DiagField<Self, A>, MaybeUninit<T::StrLen>: StrLen<SQLSMALLINT>,

Returns the current value of a field of a record of the diagnostic data structure (associated with a specified handle) that contains error, warning, and status information.

fn SQLGetDiagFieldW<A: Ident<Type = SQLSMALLINT>, T>( &self, RecNumber: NonZeroI16, DiagIdentifier: A, DiagInfoPtr: Option<&mut T>, StringLengthPtr: Option<&mut MaybeUninit<T::StrLen>>, ) -> SQLRETURN

where T: AttrGet<A> + Unicode + ?Sized + DiagField<Self, A>, MaybeUninit<T::StrLen>: StrLen<SQLSMALLINT>,

Returns the current value of a field of a record of the diagnostic data structure (associated with a specified handle) that contains error, warning, and status information.

fn SQLGetDiagRecA( &self, RecNumber: NonZeroI16, SQLState: &mut MaybeUninit<SQLSTATE<SQLCHAR>>, NativeErrorPtr: &mut impl AsMutPtr<SQLINTEGER>, MessageText: &mut OdbcStr<MaybeUninit<SQLCHAR>>, TextLengthPtr: &mut impl AsMutPtr<SQLSMALLINT>, ) -> SQLRETURN

Returns the current values of multiple fields of a diagnostic record that contains error, warning, and status information. Unlike SQLGetDiagField, which returns one diagnostic field per call, SQLGetDiagRec returns several commonly used fields of a diagnostic record, including the SQLSTATE, the native error code, and the diagnostic message text.

fn SQLGetDiagRecW( &self, RecNumber: NonZeroI16, SQLState: &mut MaybeUninit<SQLSTATE<SQLWCHAR>>, NativeErrorPtr: &mut impl AsMutPtr<SQLINTEGER>, MessageText: &mut OdbcStr<MaybeUninit<SQLWCHAR>>, TextLengthPtr: &mut impl AsMutPtr<SQLSMALLINT>, ) -> SQLRETURN

Returns the current values of multiple fields of a diagnostic record that contains error, warning, and status information. Unlike SQLGetDiagField, which returns one diagnostic field per call, SQLGetDiagRec returns several commonly used fields of a diagnostic record, including the SQLSTATE, the native error code, and the diagnostic message text.

impl<DT, V: OdbcVersion> Handle for SQLHDESC<'_, DT, V>

type Ident = SQL_HANDLE_DESC

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, T: Scalar> DescField<'buf, SQLHDESC<'conn, DT>, DT, A, SQL_OV_ODBC3_80> for [T]

where [T]: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion>,

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, CH: OdbcChar> DescField<'buf, SQLHDESC<'conn, DT>, DT, A, SQL_OV_ODBC3_80> for OdbcStr<CH>

where OdbcStr<CH>: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC3_80 as OdbcVersion>::PrevVersion>,

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, T: Scalar> DescField<'buf, SQLHDESC<'conn, DT, SQL_OV_ODBC4>, DT, A, SQL_OV_ODBC4> for [T]

where [T]: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion>,

impl<'conn, 'buf, DT: DescType<'buf>, A: Ident, CH: OdbcChar> DescField<'buf, SQLHDESC<'conn, DT, SQL_OV_ODBC4>, DT, A, SQL_OV_ODBC4> for OdbcStr<CH>

where OdbcStr<CH>: DescField<'buf, SQLHDESC<'conn, DT, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion>, DT, A, <SQL_OV_ODBC4 as OdbcVersion>::PrevVersion>,

impl<DT, V: OdbcVersion> Send for SQLHDESC<'_, DT, V>