Struct Preceding 

pub struct Preceding {
    pub offset: i64,
    pub offset_expr: Option<Box<Expression>>,
}

Defines a bound earlier than the current record in the declared ordering in sorts.

Fields

offset: i64

👎Deprecated

A strictly positive integer specifying the offset of this bound. Use CurrentRow for offset zero and Following for negative offsets.

At least one of offset and offset_expr must be set.

Deprecated: use offset_expr instead.

offset_expr: Option<Box<Expression>>

Expression specifying the distance of this bound from the current row. Its interpretation depends on WindowFunction.bounds_type:

• BOUNDS_TYPE_ROWS: evaluates to a non-negative integer number of rows. The type must be int64.
• BOUNDS_TYPE_RANGE: evaluates to a non-negative distance applied toward values earlier in the declared ordering in sorts. Its type D must be compatible with the type T of the single ordering expression, i.e. add(T, D) -> T and subtract(T, D) -> T must be defined (e.g. timestamp/interval_day, decimal/decimal, i64/i64).

A null offset expression result is invalid. When the current row’s ordering value is null, a RANGE offset bound is equivalent to CurrentRow. A negative result is invalid; a zero result is equivalent to CurrentRow. Because offset cannot represent zero, producers should emit CurrentRow rather than a zero offset_expr so that the bound remains readable by consumers that do not yet support offset_expr. Use Following for a bound after the current row.

Field references resolve against the input schema of the relation containing this window function; the expression must behave as if evaluated once per input record. It must not contain window or aggregate functions.

Trait Implementations

impl Clone for Preceding

fn clone(&self) -> Preceding

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Preceding

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

Formats the value using the given formatter.

impl Default for Preceding

fn default() -> Self

Returns the “default value” for a type.

impl Message for Preceding

fn encoded_len(&self) -> usize

Returns the encoded length of the message without a length delimiter.

fn clear(&mut self)

Clears the message, resetting all fields to their default.

fn encode(&self, buf: &mut impl BufMut) -> Result<(), EncodeError>

where Self: Sized,

Encodes the message to a buffer.

fn encode_to_vec(&self) -> Vec<u8>

where Self: Sized,

Encodes the message to a newly allocated buffer.

fn encode_length_delimited( &self, buf: &mut impl BufMut, ) -> Result<(), EncodeError>

where Self: Sized,

Encodes the message with a length-delimiter to a buffer.

fn encode_length_delimited_to_vec(&self) -> Vec<u8>

where Self: Sized,

Encodes the message with a length-delimiter to a newly allocated buffer.

fn decode(buf: impl Buf) -> Result<Self, DecodeError>

where Self: Default,

Decodes an instance of the message from a buffer.

fn decode_length_delimited(buf: impl Buf) -> Result<Self, DecodeError>

where Self: Default,

Decodes a length-delimited instance of the message from the buffer.

fn merge(&mut self, buf: impl Buf) -> Result<(), DecodeError>

where Self: Sized,

Decodes an instance of the message from a buffer, and merges it into self.

fn merge_length_delimited(&mut self, buf: impl Buf) -> Result<(), DecodeError>

where Self: Sized,

Decodes a length-delimited instance of the message from buffer, and merges it into self.

impl Name for Preceding

const NAME: &'static str = "Preceding"

Simple name for this Message. This name is the same as it appears in the source .proto file, e.g. FooBar.

const PACKAGE: &'static str = "substrait"

Package name this message type is contained in. They are domain-like and delimited by ., e.g. google.protobuf.

fn full_name() -> String

Fully-qualified unique name for this Message. It’s prefixed with the package name and names of any parent messages, e.g. google.rpc.BadRequest.FieldViolation. By default, this is the package name followed by the message name. Fully-qualified names must be unique within a domain of Type URLs.

fn type_url() -> String

Type URL for this Message, which by default is the full name with a leading slash, but may also include a leading domain name, e.g. type.googleapis.com/google.profile.Person. This can be used when serializing into the google.protobuf.Any type.

impl PartialEq for Preceding

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Preceding