Enum repr::ScalarType

pub enum ScalarType {
    Bool,
    Int16,
    Int32,
    Int64,
    Float32,
    Float64,
    Numeric {
        scale: Option<u8>,
    },
    Date,
    Time,
    Timestamp,
    TimestampTz,
    Interval,
    Bytes,
    String,
    Char {
        length: Option<usize>,
    },
    VarChar {
        length: Option<usize>,
    },
    Jsonb,
    Uuid,
    Array(Box<ScalarType>),
    List {
        element_type: Box<ScalarType>,
        custom_oid: Option<u32>,
    },
    Record {
        fields: Vec<(ColumnName, ColumnType)>,
        custom_oid: Option<u32>,
        custom_name: Option<String>,
    },
    Oid,
    Map {
        value_type: Box<ScalarType>,
        custom_oid: Option<u32>,
    },
    RegProc,
    RegType,
    RegClass,
}

The type of a Datum.

There is a direct correspondence between Datum variants and ScalarType variants.

Variants

Bool

The type of Datum::True and Datum::False.

Int16

The type of Datum::Int16.

Int32

The type of Datum::Int32.

Int64

The type of Datum::Int64.

Float32

The type of Datum::Float32.

Float64

The type of Datum::Float64.

Numeric

Fields

scale: Option<u8>

The type of Datum::Numeric.

Numeric values cannot exceed NUMERIC_DATUM_MAX_PRECISION digits of precision.

This type additionally specifies the scale of the decimal. The scale specifies the number of digits after the decimal point. The scale must be less than or equal to the maximum precision.

Date

The type of Datum::Date.

Time

The type of Datum::Time.

Timestamp

The type of Datum::Timestamp.

TimestampTz

The type of Datum::TimestampTz.

Interval

The type of Datum::Interval.

Bytes

The type of Datum::Bytes.

String

The type of Datum::String.

Char

Fields

length: Option<usize>

Stored as Datum::String, but expresses a fixed-width, blank-padded string.

Note that a length of None is used in special cases, such as creating lists.

VarChar

Fields

length: Option<usize>

Stored as Datum::String, but can optionally express a limit on the string’s length.

Jsonb

The type of a datum that may represent any valid JSON value.

Valid datum variants for this type are:

• Datum::Null
• Datum::False
• Datum::True
• Datum::String
• Datum::Float64
• Datum::List
• Datum::Map

Uuid

The type of Datum::Uuid.

Array(Box<ScalarType>)

Tuple Fields

0: Box<ScalarType>

The type of Datum::Array.

Elements within the array are of the specified type. It is illegal for the element type to be itself an array type. Array elements may always be Datum::Null.

List

Fields

element_type: Box<ScalarType>

custom_oid: Option<u32>

The type of Datum::List.

Elements within the list are of the specified type. List elements may always be Datum::Null.

Record

Fields

fields: Vec<(ColumnName, ColumnType)>

The names and types of the fields of the record, in order from left to right.

custom_oid: Option<u32>

custom_name: Option<String>

An ordered and named sequence of datums.

Oid

A PostgreSQL object identifier.

Map

Fields

value_type: Box<ScalarType>

custom_oid: Option<u32>

The type of Datum::Map

Keys within the map are always of type ScalarType::String. Values within the map are of the specified type. Values may always be Datum::Null.

RegProc

A PostgreSQL function name.

RegType

A PostgreSQL type name.

RegClass

A PostgreSQL class name.

Implementations

impl<'a> ScalarType

pub fn unwrap_numeric_scale(&self) -> Option<u8>

Returns the contained numeric scale.

Panics

Panics if the scalar type is not ScalarType::Numeric.

pub fn unwrap_list_element_type(&self) -> &ScalarType

Returns the ScalarType of elements in a ScalarType::List.

Panics

Panics if called on anything other than a ScalarType::List.

pub fn unwrap_list_n_dims(&self) -> usize

Returns number of dimensions/axes (also known as “rank”) on a ScalarType::List.

Panics

Panics if called on anything other than a ScalarType::List.

pub fn default_embedded_value(&self) -> ScalarType

Returns self with any embedded values set to a value appropriate for a collection of the type. Namely, this should set optional scales or limits to None.

pub fn unwrap_array_element_type(&self) -> &ScalarType

Returns the ScalarType of elements in a ScalarType::Array.

Panics

Panics if called on anything other than a ScalarType::Array.

pub fn unwrap_map_value_type(&self) -> &ScalarType

Returns the ScalarType of values in a ScalarType::Map.

Panics

Panics if called on anything other than a ScalarType::Map.

pub fn unwrap_char_varchar_length(&self) -> Option<usize>

Returns the length of a ScalarType::Char or ScalarType::VarChar.

Panics

Panics if called on anything other than a ScalarType::Char or ScalarType::VarChar.

pub fn nullable(self, nullable: bool) -> ColumnType

Derives a column type from this scalar type with the specified nullability.

pub fn is_vec(&self) -> bool

Returns whether or not self is a vector-like type, i.e. ScalarType::List or ScalarType::Array, irrespective of its element type.

pub fn is_custom_type(&self) -> bool

pub fn base_eq(&self, other: &ScalarType) -> bool

Determines equality among scalar types that acknowledges custom OIDs, but ignores other embedded values.

In most situations, you want to use base_eq rather than ScalarType’s implementation of Eq. base_eq expresses the semantics of direct type interoperability whereas Eq expresses an exact comparison between the values.

For instance, base_eq signals that e.g. two ScalarType::Numeric values can be added together, irrespective of their embedded scale. In contrast, two Numeric values with different scales are never Eq to one another.

pub fn is_string_like(&self) -> bool

Trait Implementations

impl Clone for ScalarType

fn clone(&self) -> ScalarType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ScalarType

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ScalarType

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl<'__enum_kinds1> From<&'__enum_kinds1 ScalarType> for ScalarBaseType

fn from(_value: &'__enum_kinds1 ScalarType) -> Self

Performs the conversion.

impl<'__enum_kinds1> From<ScalarType> for ScalarBaseType

fn from(value: ScalarType) -> Self

Performs the conversion.

impl Hash for ScalarType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl MzReflect for ScalarType

fn add_to_reflected_type_info(rti: &mut ReflectedTypeInfo)

Adds names and types of the fields of the struct or enum to rti.

impl Ord for ScalarType

fn cmp(&self, other: &ScalarType) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<ScalarType> for ScalarType

fn eq(&self, other: &ScalarType) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &ScalarType) -> bool

This method tests for !=.

impl PartialOrd<ScalarType> for ScalarType

fn partial_cmp(&self, other: &ScalarType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for ScalarType

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.

impl Eq for ScalarType

impl StructuralEq for ScalarType

impl StructuralPartialEq for ScalarType