public sealed class QueryOptions : IMessage<ExecuteSqlRequest.Types.QueryOptions>, IEquatable<ExecuteSqlRequest.Types.QueryOptions>, IDeepCloneable<ExecuteSqlRequest.Types.QueryOptions>, IBufferMessage, IMessage
Query optimizer configuration.
Implements
IMessage<ExecuteSqlRequest.Types.QueryOptions>, IEquatable<ExecuteSqlRequest.Types.QueryOptions>, IDeepCloneable<ExecuteSqlRequest.Types.QueryOptions>, IBufferMessage, IMessageNamespace
Google.Cloud.Spanner.V1Assembly
Google.Cloud.Spanner.V1.dll
Constructors
QueryOptions()
public QueryOptions()
QueryOptions(ExecuteSqlRequest.Types.QueryOptions)
public QueryOptions(ExecuteSqlRequest.Types.QueryOptions other)
Parameter | |
---|---|
Name | Description |
other | ExecuteSqlRequest.Types.QueryOptions |
Properties
OptimizerStatisticsPackage
public string OptimizerStatisticsPackage { get; set; }
Query optimizer statistics package to use.
This parameter allows individual queries to use a different query optimizer statistics.
Specifying latest
as a value instructs Cloud Spanner to use the latest
generated statistics package. If not specified, Cloud Spanner uses
statistics package set at the database level options, or latest 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
SPANNER_SYS.OPTIMIZER_STATISTICS_PACKAGES
.
Executing a SQL statement with an invalid optimizer statistics package
or with statistics package that allows garbage collection fails with
an INVALID_ARGUMENT
error.
Property Value | |
---|---|
Type | Description |
String |
OptimizerVersion
public string OptimizerVersion { get; set; }
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.
Property Value | |
---|---|
Type | Description |
String |