queryservice

Documentation

Overview

Package queryservice contains the interface for the service definition of the Query Service.

Index

• func CallCorrectSplitQuery(queryService QueryService, useSplitQueryV2 bool, ctx context.Context, ...) ([]querytypes.QuerySplit, error)
• type QueryService

Functions

func CallCorrectSplitQuery

func CallCorrectSplitQuery(
	queryService QueryService,
	useSplitQueryV2 bool,
	ctx context.Context,
	target *querypb.Target,
	sql string,
	bindVariables map[string]interface{},
	splitColumns []string,
	splitCount int64,
	numRowsPerQueryPart int64,
	algorithm querypb.SplitQueryRequest_Algorithm,
) ([]querytypes.QuerySplit, error)

CallCorrectSplitQuery calls the correct SplitQuery. This trivial logic is encapsulated in a function here so it can be easily tested. TODO(erez): Remove once the migration to SplitQueryV2 is done.

Types

type QueryService

type QueryService interface {

	// Begin returns the transaction id to use for further operations
	Begin(ctx context.Context, target *querypb.Target) (int64, error)

	// Commit commits the current transaction
	Commit(ctx context.Context, target *querypb.Target, transactionID int64) error

	// Rollback aborts the current transaction
	Rollback(ctx context.Context, target *querypb.Target, transactionID int64) error

	Execute(ctx context.Context, target *querypb.Target, sql string, bindVariables map[string]interface{}, transactionID int64) (*sqltypes.Result, error)
	StreamExecute(ctx context.Context, target *querypb.Target, sql string, bindVariables map[string]interface{}, sendReply func(*sqltypes.Result) error) error
	ExecuteBatch(ctx context.Context, target *querypb.Target, queries []querytypes.BoundQuery, asTransaction bool, transactionID int64) ([]sqltypes.Result, error)

	// SplitQuery is a map reduce helper function
	// TODO(erez): Remove this and rename the following func to SplitQuery
	// once we migrate to SplitQuery V2.
	SplitQuery(ctx context.Context, target *querypb.Target, sql string, bindVariables map[string]interface{}, splitColumn string, splitCount int64) ([]querytypes.QuerySplit, error)

	// SplitQueryV2 is a MapReduce helper function.
	// This is version of SplitQuery supports multiple algorithms and multiple split columns.
	// See the documentation of SplitQueryRequest in 'proto/vtgate.proto' for more information.
	SplitQueryV2(
		ctx context.Context,
		target *querypb.Target,
		sql string,
		bindVariables map[string]interface{},
		splitColumns []string,
		splitCount int64,
		numRowsPerQueryPart int64,
		algorithm querypb.SplitQueryRequest_Algorithm,
	) ([]querytypes.QuerySplit, error)

	// StreamHealthRegister registers a listener for StreamHealth
	StreamHealthRegister(chan<- *querypb.StreamHealthResponse) (int, error)

	// StreamHealthUnregister unregisters a listener for StreamHealth
	StreamHealthUnregister(int) error

	// Helper for RPC panic handling: call this in a defer statement
	// at the beginning of each RPC handling method.
	HandlePanic(*error)
}

QueryService is the interface implemented by the tablet's query service.