Struct ReadRequest

pub struct ReadRequest {

    pub columns: Option<Vec<String>>,
    pub data_boost_enabled: Option<bool>,
    pub directed_read_options: Option<DirectedReadOptions>,
    pub index: Option<String>,
    pub key_set: Option<KeySet>,
    pub limit: Option<i64>,
    pub lock_hint: Option<String>,
    pub order_by: Option<String>,
    pub partition_token: Option<Vec<u8>>,
    pub request_options: Option<RequestOptions>,
    pub resume_token: Option<Vec<u8>>,
    pub table: Option<String>,
    pub transaction: Option<TransactionSelector>,
}

The request for Read and StreamingRead.

Activities

This type is used in activities, which are methods you may call on this type or where this type is involved in. The list links the activity name, along with information about where it is used (one of request and response).

• instances databases sessions read projects (request)
• instances databases sessions streaming read projects (request)

Fields

columns: Option<Vec<String>>

Required. The columns of table to be returned for each row matching this request.

data_boost_enabled: Option<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.

directed_read_options: Option<DirectedReadOptions>

Directed read options for this request.

index: Option<String>

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

key_set: Option<KeySet>

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in table to be yielded, unless index is present. If index is present, then key_set instead names index keys in index. If the partition_token field is empty, rows are yielded in table primary key order (if index is empty) or index key order (if index is non-empty). If the 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: Option<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.

lock_hint: Option<String>

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

order_by: Option<String>

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).

partition_token: Option<Vec<u8>>

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.

resume_token: Option<Vec<u8>>

If this request is resuming a previously interrupted read, resume_token should be copied from the last 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.

table: Option<String>

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

transaction: Option<TransactionSelector>

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

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() -> ReadRequest

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ReadRequest

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ReadRequest

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl RequestValue for ReadRequest