google::cloud::spanner::ProfileQueryResult Class Reference

Represents the stream of Rows and profile stats returned from spanner::Client::ProfileQuery(). More...

#include <google/cloud/spanner/results.h>

Public Member Functions
	ProfileQueryResult ()=default
	ProfileQueryResult (std::unique_ptr< ResultSourceInterface > source)
	ProfileQueryResult (ProfileQueryResult &&)=default
ProfileQueryResult &	operator= (ProfileQueryResult &&)=default
RowStreamIterator	begin ()
	Returns a RowStreamIterator defining the beginning of this result set. More...
RowStreamIterator	end ()
	Returns a RowStreamIterator defining the end of this result set. More...
absl::optional< Timestamp >	ReadTimestamp () const
	Retrieves the timestamp at which the read occurred. More...
absl::optional< std::unordered_map< std::string, std::string > >	ExecutionStats () const
	Returns a collection of key value pair statistics for the SQL statement execution. More...
absl::optional< spanner::ExecutionPlan >	ExecutionPlan () const
	Returns the plan of execution for the SQL statement. More...

Detailed Description

Represents the stream of Rows and profile stats returned from spanner::Client::ProfileQuery().

This is a range defined by the Input Iterators returned from its begin() and end() members. Callers may directly iterate the ProfileQueryResult instance, which will return a sequence of StatusOr<Row> objects.

For convenience, callers may wrap instances in a StreamOf<std::tuple<...>> object, which will automatically parse each Row into a std::tuple with the specified types.

Example:

  namespace spanner = ::google::cloud::spanner;
  spanner::SqlStatement select(
      "SELECT AlbumId, AlbumTitle, MarketingBudget"
      " FROM Albums"
      " WHERE AlbumTitle >= 'Aardvark' AND AlbumTitle < 'Goo'");
  auto profile_query_result = client.ProfileQuery(std::move(select));
  for (auto& row : profile_query_result) {
    if (!row) throw std::move(row).status();
    // Discard rows for brevity in this example.
  }
 
  // Stats are only available after all rows from the result have been read.
  auto execution_stats = profile_query_result.ExecutionStats();
  if (execution_stats) {
    for (auto const& stat : *execution_stats) {
      std::cout << stat.first << ":\t" << stat.second << "\n";
    }
  }

Constructor & Destructor Documentation

ProfileQueryResult() [1/3]

google::cloud::spanner::ProfileQueryResult::ProfileQueryResult ( )

default

ProfileQueryResult() [2/3]

google::cloud::spanner::ProfileQueryResult::ProfileQueryResult ( std::unique_ptr< ResultSourceInterface >  source )

inlineexplicit

ProfileQueryResult() [3/3]

google::cloud::spanner::ProfileQueryResult::ProfileQueryResult ( ProfileQueryResult &&  )

default

Member Function Documentation

begin()

RowStreamIterator google::cloud::spanner::ProfileQueryResult::begin ( )

inline

Returns a RowStreamIterator defining the beginning of this result set.

end()

RowStreamIterator google::cloud::spanner::ProfileQueryResult::end ( )

inline

Returns a RowStreamIterator defining the end of this result set.

ExecutionPlan()

absl::optional< spanner::ExecutionPlan > google::cloud::spanner::ProfileQueryResult::ExecutionPlan

(

)

const

Returns the plan of execution for the SQL statement.

ExecutionStats()

absl::optional< std::unordered_map< std::string, std::string > > google::cloud::spanner::ProfileQueryResult::ExecutionStats

(

)

const

Returns a collection of key value pair statistics for the SQL statement execution.

Note

Only available when the statement is executed and all results have been read.

operator=()

ProfileQueryResult & google::cloud::spanner::ProfileQueryResult::operator= ( ProfileQueryResult &&  )

default

ReadTimestamp()

absl::optional< Timestamp > google::cloud::spanner::ProfileQueryResult::ReadTimestamp

(

)

const

Retrieves the timestamp at which the read occurred.

Note

Only available if a read-only transaction was used.