Struct diesel::sql_types::Nullable

pub struct Nullable<ST: NotNull>(_);

The nullable SQL type.

This wraps another SQL type to indicate that it can be null. By default all values are assumed to be NOT NULL.

ToSql impls

• Any T which implements ToSql<ST>
• Option<T> for any T which implements ToSql<ST>

FromSql impls

• Option<T> for any T which implements FromSql<ST>

Trait Implementations

impl<T, ST, DB> Queryable<Nullable<ST>, DB> for Option<T> where
    T: Queryable<ST, DB>,
    DB: Backend,
    Option<T::Row>: FromSqlRow<Nullable<ST>, DB>,
    ST: NotNull, 

type Row = Option<T::Row>

The Rust type you'd like to map from.

fn build(row: Self::Row) -> Self

Construct an instance of this type

impl<T, ST, DB> FromSql<Nullable<ST>, DB> for Option<T> where
    T: FromSql<ST, DB>,
    DB: Backend,
    ST: NotNull, 

fn from_sql(bytes: Option<&DB::RawValue>) -> Result<Self>

See the trait documentation.

impl<T, ST, DB> FromSqlRow<Nullable<ST>, DB> for Option<T> where
    T: FromSqlRow<ST, DB>,
    DB: Backend,
    ST: NotNull, 

const FIELDS_NEEDED: usize

The number of fields that this type will consume. Must be equal to the number of times you would call row.take() in build_from_row

fn build_from_row<R: Row<DB>>(row: &mut R) -> Result<Self>

See the trait documentation.

impl AsExpression<Nullable<Timestamp>> for now

type Expression = Coerce<now, Nullable<Timestamp>>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Timestamp>> for &'expr SystemTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Timestamp>> for &'expr2 &'expr SystemTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Timestamp>> for SystemTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Date>> for &'expr NaiveDate

type Expression = Bound<Nullable<Date>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Date>> for &'expr2 &'expr NaiveDate

type Expression = Bound<Nullable<Date>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Date>> for NaiveDate

type Expression = Bound<Nullable<Date>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Time>> for &'expr NaiveTime

type Expression = Bound<Nullable<Time>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Time>> for &'expr2 &'expr NaiveTime

type Expression = Bound<Nullable<Time>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Time>> for NaiveTime

type Expression = Bound<Nullable<Time>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Timestamp>> for &'expr NaiveDateTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Timestamp>> for &'expr2 &'expr NaiveDateTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Timestamp>> for NaiveDateTime

type Expression = Bound<Nullable<Timestamp>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Datetime>> for &'expr NaiveDateTime

type Expression = Bound<Nullable<Datetime>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Datetime>> for &'expr2 &'expr NaiveDateTime

type Expression = Bound<Nullable<Datetime>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Datetime>> for NaiveDateTime

type Expression = Bound<Nullable<Datetime>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<T, ST> AsExpression<Nullable<ST>> for Option<T> where
    ST: NotNull, 

type Expression = Bound<Nullable<ST>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'a, T, ST> AsExpression<Nullable<ST>> for &'a Option<T> where
    ST: NotNull, 

type Expression = Bound<Nullable<ST>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Bool>> for &'expr bool

type Expression = Bound<Nullable<Bool>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Bool>> for &'expr2 &'expr bool

type Expression = Bound<Nullable<Bool>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Bool>> for bool

type Expression = Bound<Nullable<Bool>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<TinyInt>> for &'expr i8

type Expression = Bound<Nullable<TinyInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<TinyInt>> for &'expr2 &'expr i8

type Expression = Bound<Nullable<TinyInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<TinyInt>> for i8

type Expression = Bound<Nullable<TinyInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<SmallInt>> for &'expr i16

type Expression = Bound<Nullable<SmallInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<SmallInt>> for &'expr2 &'expr i16

type Expression = Bound<Nullable<SmallInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<SmallInt>> for i16

type Expression = Bound<Nullable<SmallInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Integer>> for &'expr i32

type Expression = Bound<Nullable<Integer>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Integer>> for &'expr2 &'expr i32

type Expression = Bound<Nullable<Integer>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Integer>> for i32

type Expression = Bound<Nullable<Integer>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<BigInt>> for &'expr i64

type Expression = Bound<Nullable<BigInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<BigInt>> for &'expr2 &'expr i64

type Expression = Bound<Nullable<BigInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<BigInt>> for i64

type Expression = Bound<Nullable<BigInt>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Unsigned<TinyInt>>> for &'expr u8

type Expression = Bound<Nullable<Unsigned<TinyInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Unsigned<TinyInt>>> for &'expr2 &'expr u8

type Expression = Bound<Nullable<Unsigned<TinyInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Unsigned<TinyInt>>> for u8

type Expression = Bound<Nullable<Unsigned<TinyInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Unsigned<SmallInt>>> for &'expr u16

type Expression = Bound<Nullable<Unsigned<SmallInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Unsigned<SmallInt>>> for &'expr2 &'expr u16

type Expression = Bound<Nullable<Unsigned<SmallInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Unsigned<SmallInt>>> for u16

type Expression = Bound<Nullable<Unsigned<SmallInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Unsigned<Integer>>> for &'expr u32

type Expression = Bound<Nullable<Unsigned<Integer>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Unsigned<Integer>>> for &'expr2 &'expr u32

type Expression = Bound<Nullable<Unsigned<Integer>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Unsigned<Integer>>> for u32

type Expression = Bound<Nullable<Unsigned<Integer>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Unsigned<BigInt>>> for &'expr u64

type Expression = Bound<Nullable<Unsigned<BigInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Unsigned<BigInt>>> for &'expr2 &'expr u64

type Expression = Bound<Nullable<Unsigned<BigInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Unsigned<BigInt>>> for u64

type Expression = Bound<Nullable<Unsigned<BigInt>>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Float>> for &'expr f32

type Expression = Bound<Nullable<Float>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Float>> for &'expr2 &'expr f32

type Expression = Bound<Nullable<Float>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Float>> for f32

type Expression = Bound<Nullable<Float>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Double>> for &'expr f64

type Expression = Bound<Nullable<Double>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Double>> for &'expr2 &'expr f64

type Expression = Bound<Nullable<Double>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Double>> for f64

type Expression = Bound<Nullable<Double>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Text>> for &'expr String

type Expression = Bound<Nullable<Text>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Text>> for &'expr2 &'expr String

type Expression = Bound<Nullable<Text>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Text>> for String

type Expression = Bound<Nullable<Text>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Text>> for &'expr str

type Expression = Bound<Nullable<Text>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Text>> for &'expr2 &'expr str

type Expression = Bound<Nullable<Text>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Binary>> for &'expr Vec<u8>

type Expression = Bound<Nullable<Binary>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Binary>> for &'expr2 &'expr Vec<u8>

type Expression = Bound<Nullable<Binary>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl AsExpression<Nullable<Binary>> for Vec<u8>

type Expression = Bound<Nullable<Binary>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr> AsExpression<Nullable<Binary>> for &'expr [u8]

type Expression = Bound<Nullable<Binary>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<'expr2, 'expr> AsExpression<Nullable<Binary>> for &'expr2 &'expr [u8]

type Expression = Bound<Nullable<Binary>, Self>

The expression being returned

fn as_expression(self) -> Self::Expression

Perform the conversion

impl<T> QueryId for Nullable<T> where
    T: QueryId + NotNull, 

type QueryId = T::QueryId

A type which uniquely represents Self in a SQL query.

const HAS_STATIC_QUERY_ID: bool

Can the SQL generated by Self be uniquely identified by its type?

fn query_id() -> Option<TypeId>

Returns the type id of Self::QueryId if Self::HAS_STATIC_QUERY_ID. Returns None otherwise.

impl<__DB> ToSql<Nullable<Timestamp>, __DB> for SystemTime where
    __DB: Backend,
    Self: ToSql<Timestamp, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Date>, __DB> for NaiveDate where
    __DB: Backend,
    Self: ToSql<Date, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Time>, __DB> for NaiveTime where
    __DB: Backend,
    Self: ToSql<Time, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Timestamp>, __DB> for NaiveDateTime where
    __DB: Backend,
    Self: ToSql<Timestamp, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Datetime>, __DB> for NaiveDateTime where
    __DB: Backend,
    Self: ToSql<Datetime, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<T, ST, DB> ToSql<Nullable<ST>, DB> for Option<T> where
    T: ToSql<ST, DB>,
    DB: Backend,
    ST: NotNull, 

fn to_sql<W: Write>(&self, out: &mut Output<W, DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Bool>, __DB> for bool where
    __DB: Backend,
    Self: ToSql<Bool, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<TinyInt>, __DB> for i8 where
    __DB: Backend,
    Self: ToSql<TinyInt, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<SmallInt>, __DB> for i16 where
    __DB: Backend,
    Self: ToSql<SmallInt, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Integer>, __DB> for i32 where
    __DB: Backend,
    Self: ToSql<Integer, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<BigInt>, __DB> for i64 where
    __DB: Backend,
    Self: ToSql<BigInt, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Unsigned<TinyInt>>, __DB> for u8 where
    __DB: Backend,
    Self: ToSql<Unsigned<TinyInt>, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Unsigned<SmallInt>>, __DB> for u16 where
    __DB: Backend,
    Self: ToSql<Unsigned<SmallInt>, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Unsigned<Integer>>, __DB> for u32 where
    __DB: Backend,
    Self: ToSql<Unsigned<Integer>, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Unsigned<BigInt>>, __DB> for u64 where
    __DB: Backend,
    Self: ToSql<Unsigned<BigInt>, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Float>, __DB> for f32 where
    __DB: Backend,
    Self: ToSql<Float, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Double>, __DB> for f64 where
    __DB: Backend,
    Self: ToSql<Double, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Text>, __DB> for String where
    __DB: Backend,
    Self: ToSql<Text, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Text>, __DB> for str where
    __DB: Backend,
    Self: ToSql<Text, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Binary>, __DB> for Vec<u8> where
    __DB: Backend,
    Self: ToSql<Binary, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<__DB> ToSql<Nullable<Binary>, __DB> for [u8] where
    __DB: Backend,
    Self: ToSql<Binary, __DB>, 

fn to_sql<W: Write>(&self, out: &mut Output<W, __DB>) -> Result

See the trait documentation.

impl<T> Foldable for Nullable<T> where
    T: Foldable + NotNull, 

type Sum = T::Sum

The SQL type of sum(this_type)

type Avg = T::Avg

The SQL type of avg(this_type)

impl<T> Add for Nullable<T> where
    T: Add + NotNull,
    T::Rhs: NotNull,
    T::Output: NotNull, 

type Rhs = Nullable<T::Rhs>

The SQL type which can be added to this one

type Output = Nullable<T::Output>

The SQL type of the result of adding Rhs to Self

impl<T> Sub for Nullable<T> where
    T: Sub + NotNull,
    T::Rhs: NotNull,
    T::Output: NotNull, 

type Rhs = Nullable<T::Rhs>

The SQL type which can be subtracted from this one

type Output = Nullable<T::Output>

The SQL type of the result of subtracting Rhs from Self

impl<T> Mul for Nullable<T> where
    T: Mul + NotNull,
    T::Rhs: NotNull,
    T::Output: NotNull, 

type Rhs = Nullable<T::Rhs>

The SQL type which this can be multiplied by

type Output = Nullable<T::Output>

The SQL type of the result of multiplying Self by Rhs

impl<T> Div for Nullable<T> where
    T: Div + NotNull,
    T::Rhs: NotNull,
    T::Output: NotNull, 

type Rhs = Nullable<T::Rhs>

The SQL type which this one can be divided by

type Output = Nullable<T::Output>

The SQL type of the result of dividing Self by Rhs

impl<T: SqlOrd + NotNull> SqlOrd for Nullable<T>

impl<T, DB> HasSqlType<Nullable<T>> for DB where
    DB: Backend + HasSqlType<T>,
    T: NotNull, 

fn metadata(lookup: &DB::MetadataLookup) -> DB::TypeMetadata

Fetch the metadata for the given type

fn row_metadata(out: &mut Vec<DB::TypeMetadata>, lookup: &DB::MetadataLookup)

fn mysql_row_metadata(
    out: &mut Vec<(DB::TypeMetadata, IsSigned)>,
    lookup: &DB::MetadataLookup
)

impl<T: NotNull> IntoNullable for Nullable<T>

type Nullable = Nullable<T>

The nullable representation of this type.

impl<T: NotNull + SingleValue> SingleValue for Nullable<T>

impl<ST: Copy + NotNull> Copy for Nullable<ST>

impl<ST: Default + NotNull> Default for Nullable<ST>

fn default() -> Nullable<ST>

Returns the "default value" for a type.

impl<ST: Clone + NotNull> Clone for Nullable<ST>

fn clone(&self) -> Nullable<ST>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<ST: Debug + NotNull> Debug for Nullable<ST>

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

Formats the value using the given formatter.