Struct gapi_grpc::google::spanner::v1::KeyRange

pub struct KeyRange {
    pub start_key_type: Option<StartKeyType>,
    pub end_key_type: Option<EndKeyType>,
}

KeyRange represents a range of rows in a table or index.

A range has a start key and an end key. These keys can be open or closed, indicating if the range includes rows with that key.

Keys are represented by lists, where the ith value in the list corresponds to the ith component of the table or index primary key. Individual values are encoded as described [here][google.spanner.v1.TypeCode].

For example, consider the following table definition:

CREATE TABLE UserEvents (
  UserName STRING(MAX),
  EventDate STRING(10)
) PRIMARY KEY(UserName, EventDate);

The following keys name rows in this table:

["Bob", "2014-09-23"]
["Alfred", "2015-06-12"]

Since the UserEvents table’s PRIMARY KEY clause names two columns, each UserEvents key has two elements; the first is the UserName, and the second is the EventDate.

Key ranges with multiple components are interpreted lexicographically by component using the table or index key’s declared sort order. For example, the following range returns all events for user "Bob" that occurred in the year 2015:

"start_closed": ["Bob", "2015-01-01"]
"end_closed": ["Bob", "2015-12-31"]

Start and end keys can omit trailing key components. This affects the inclusion and exclusion of rows that exactly match the provided key components: if the key is closed, then rows that exactly match the provided components are included; if the key is open, then rows that exactly match are not included.

For example, the following range includes all events for "Bob" that occurred during and after the year 2000:

"start_closed": ["Bob", "2000-01-01"]
"end_closed": ["Bob"]

The next example retrieves all events for "Bob":

"start_closed": ["Bob"]
"end_closed": ["Bob"]

To retrieve events before the year 2000:

"start_closed": ["Bob"]
"end_open": ["Bob", "2000-01-01"]

The following range includes all rows in the table:

"start_closed": []
"end_closed": []

This range returns all users whose UserName begins with any character from A to C:

"start_closed": ["A"]
"end_open": ["D"]

This range returns all users whose UserName begins with B:

"start_closed": ["B"]
"end_open": ["C"]

Key ranges honor column sort order. For example, suppose a table is defined as follows:

CREATE TABLE DescendingSortedTable {
  Key INT64,
  ...
) PRIMARY KEY(Key DESC);

The following range retrieves all rows with key values between 1 and 100 inclusive:

"start_closed": ["100"]
"end_closed": ["1"]

Note that 100 is passed as the start, and 1 is passed as the end, because Key is a descending column in the schema.

Fields

start_key_type: Option<StartKeyType>

The start key must be provided. It can be either closed or open.

end_key_type: Option<EndKeyType>

The end key must be provided. It can be either closed or open.

Trait Implementations

impl Clone for KeyRange

fn clone(&self) -> KeyRange

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for KeyRange

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

Formats the value using the given formatter.

impl Default for KeyRange

fn default() -> KeyRange

Returns the “default value” for a type.

impl Message for KeyRange

fn encode_raw<B>(&self, buf: &mut B) where
    B: BufMut, 

fn merge_field<B>(
    &mut self,
    tag: u32,
    wire_type: WireType,
    buf: &mut B,
    ctx: DecodeContext
) -> Result<(), DecodeError> where
    B: Buf, 

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.

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

Encodes the message to a buffer.

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

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

pub fn decode<B>(buf: B) -> Result<Self, DecodeError> where
    Self: Default,
    B: Buf, 

Decodes an instance of the message from a buffer.

pub fn decode_length_delimited<B>(buf: B) -> Result<Self, DecodeError> where
    Self: Default,
    B: Buf, 

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

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

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

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

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

impl PartialEq<KeyRange> for KeyRange

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

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

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

This method tests for !=.

impl StructuralPartialEq for KeyRange