Struct google_api_proto::google::spanner::v1::ReadRequest

pub struct ReadRequest {

    pub session: String,
    pub transaction: Option<TransactionSelector>,
    pub table: String,
    pub index: String,
    pub columns: Vec<String>,
    pub key_set: Option<KeySet>,
    pub limit: i64,
    pub resume_token: Bytes,
    pub partition_token: Bytes,
    pub request_options: Option<RequestOptions>,
    pub directed_read_options: Option<DirectedReadOptions>,
    pub data_boost_enabled: bool,
    pub order_by: i32,
    pub lock_hint: i32,
}

The request for [Read][google.spanner.v1.Spanner.Read] and [StreamingRead][google.spanner.v1.Spanner.StreamingRead].

Fields

session: String

Required. The session in which the read should be performed.

transaction: Option<TransactionSelector>

The transaction to use. If none is provided, the default is a temporary read-only transaction with strong concurrency.

table: String

Required. The name of the table in the database to be read.

index: String

If non-empty, the name of an index on [table][google.spanner.v1.ReadRequest.table]. This index is used instead of the table primary key when interpreting [key_set][google.spanner.v1.ReadRequest.key_set] and sorting result rows. See [key_set][google.spanner.v1.ReadRequest.key_set] for further information.

columns: Vec<String>

Required. The columns of [table][google.spanner.v1.ReadRequest.table] to be returned for each row matching this request.

key_set: Option<KeySet>

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in [table][google.spanner.v1.ReadRequest.table] to be yielded, unless [index][google.spanner.v1.ReadRequest.index] is present. If [index][google.spanner.v1.ReadRequest.index] is present, then [key_set][google.spanner.v1.ReadRequest.key_set] instead names index keys in [index][google.spanner.v1.ReadRequest.index].

If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is empty, rows are yielded in table primary key order (if [index][google.spanner.v1.ReadRequest.index] is empty) or index key order (if [index][google.spanner.v1.ReadRequest.index] is non-empty). If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is not empty, rows will be yielded in an unspecified order.

It is not an error for the key_set to name rows that do not exist in the database. Read yields nothing for nonexistent rows.

limit: i64

If greater than zero, only the first limit rows are yielded. If limit is zero, the default is no limit. A limit cannot be specified if partition_token is set.

resume_token: Bytes

If this request is resuming a previously interrupted read, resume_token should be copied from the last [PartialResultSet][google.spanner.v1.PartialResultSet] yielded before the interruption. Doing this enables the new read to resume where the last read left off. The rest of the request parameters must exactly match the request that yielded this token.

partition_token: Bytes

If present, results will be restricted to the specified partition previously created using PartitionRead(). There must be an exact match for the values of fields common to this message and the PartitionReadRequest message used to create this partition_token.

request_options: Option<RequestOptions>

Common options for this request.

directed_read_options: Option<DirectedReadOptions>

Directed read options for this request.

data_boost_enabled: bool

If this is for a partitioned read and this field is set to true, the request is executed with Spanner Data Boost independent compute resources.

If the field is set to true but the request does not set partition_token, the API returns an INVALID_ARGUMENT error.

order_by: i32

Optional. Order for the returned rows.

By default, Spanner will return result rows in primary key order except for PartitionRead requests. For applications that do not require rows to be returned in primary key (ORDER_BY_PRIMARY_KEY) order, setting ORDER_BY_NO_ORDER option allows Spanner to optimize row retrieval, resulting in lower latencies in certain cases (e.g. bulk point lookups).

lock_hint: i32

Optional. Lock Hint for the request, it can only be used with read-write transactions.

Implementations

impl ReadRequest

pub fn order_by(&self) -> OrderBy

Returns the enum value of order_by, or the default if the field is set to an invalid enum value.

pub fn set_order_by(&mut self, value: OrderBy)

Sets order_by to the provided enum value.

pub fn lock_hint(&self) -> LockHint

Returns the enum value of lock_hint, or the default if the field is set to an invalid enum value.

pub fn set_lock_hint(&mut self, value: LockHint)

Sets lock_hint to the provided enum value.

Trait Implementations

impl Clone for ReadRequest

fn clone(&self) -> ReadRequest

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ReadRequest

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

Formats the value using the given formatter.

impl Default for ReadRequest

fn default() -> Self

Returns the “default value” for a type.

impl Message for ReadRequest

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 PartialEq for ReadRequest

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

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

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for ReadRequest