Struct google_cloud_googleapis::spanner::v1::execute_sql_request::QueryOptions

pub struct QueryOptions {
    pub optimizer_version: String,
    pub optimizer_statistics_package: String,
}

Query optimizer configuration.

Fields

optimizer_version: String

An option to control the selection of optimizer version.

This parameter allows individual queries to pick different query optimizer versions.

Specifying latest as a value instructs Cloud Spanner to use the latest supported query optimizer version. If not specified, Cloud Spanner uses the optimizer version set at the database level options. Any other positive integer (from the list of supported optimizer versions) overrides the default optimizer version for query execution.

The list of supported optimizer versions can be queried from SPANNER_SYS.SUPPORTED_OPTIMIZER_VERSIONS.

Executing a SQL statement with an invalid optimizer version fails with an INVALID_ARGUMENT error.

See https://cloud.google.com/spanner/docs/query-optimizer/manage-query-optimizer for more information on managing the query optimizer.

The optimizer_version statement hint has precedence over this setting.

optimizer_statistics_package: String

An option to control the selection of optimizer statistics package.

This parameter allows individual queries to use a different query optimizer statistics package.

Specifying latest as a value instructs Cloud Spanner to use the latest generated statistics package. If not specified, Cloud Spanner uses the statistics package set at the database level options, or the latest package if the database option is not set.

The statistics package requested by the query has to be exempt from garbage collection. This can be achieved with the following DDL statement:

ALTER STATISTICS <package_name> SET OPTIONS (allow_gc=false)

The list of available statistics packages can be queried from INFORMATION_SCHEMA.SPANNER_STATISTICS.

Executing a SQL statement with an invalid optimizer statistics package or with a statistics package that allows garbage collection fails with an INVALID_ARGUMENT error.

Trait Implementations

impl Clone for QueryOptions

fn clone(&self) -> QueryOptions

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for QueryOptions

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

Formats the value using the given formatter.

impl Default for QueryOptions

fn default() -> Self

Returns the “default value” for a type.

impl Message for QueryOptions

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

Encodes the message to a buffer.

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

Encodes the message to a newly allocated buffer.

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

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

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

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

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

Decodes an instance of the message from a buffer.

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

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

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.

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<QueryOptions> for QueryOptions

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

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

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

This method tests for !=.

impl StructuralPartialEq for QueryOptions