sqlannotation

Documentation

Overview

Package sqlannotation provides functions for annotating DML statements with keyspace-id comments and parsing them. These annotations are used during filtered-replication to route the DML statement to the correct shard. TOOD(erez): Move the code for the "_stream" annotations from vttablet to here.

Index

• Constants
• func AddKeyspaceIDs(sql string, keyspaceIDs [][]byte, marginComments string) string
• func AnnotateIfDML(sql string, keyspaceIDs [][]byte) string
• func ExtractKeyspaceIDS(sql string) (keyspaceIDs [][]byte, err error)
• type ExtractKeySpaceIDError
  • func (err ExtractKeySpaceIDError) Error() string

Constants

const (
	ExtractKeySpaceIDParseError                 = iota
	ExtractKeySpaceIDReplicationUnfriendlyError = iota
)

Possible values for ExtractKeySpaceIDError.Kind

Functions

func AddKeyspaceIDs

func AddKeyspaceIDs(sql string, keyspaceIDs [][]byte, marginComments string) string

AddKeyspaceIDs returns a copy of 'sql' annotated with the given keyspace id. It also appends the additional marginComments, if any.

func AnnotateIfDML

func AnnotateIfDML(sql string, keyspaceIDs [][]byte) string

AnnotateIfDML annotates 'sql' based on 'keyspaceIDs'

If 'sql' is not a DML statement no annotation is added. If 'sql' is a DML statement and contains exactly one keyspaceID

it is used to annotate 'sql'

Otherwise 'sql' is annotated as replication-unfriendly.

func ExtractKeyspaceIDS

func ExtractKeyspaceIDS(sql string) (keyspaceIDs [][]byte, err error)

ExtractKeyspaceIDS parses the annotation of the given statement and tries to extract the keyspace id. If a keyspace-id comment exists 'keyspaceID' is set to the parsed keyspace id and err is set to nil; otherwise, if a filtered-replication-unfriendly comment exists or some other parsing error occured, keyspaceID is set to nil and err is set to a non-nil error value.

Types

type ExtractKeySpaceIDError

type ExtractKeySpaceIDError struct {
	Kind    int
	Message string
}

ExtractKeySpaceIDError is the error type returned from ExtractKeySpaceID Kind is a numeric code for the error (see constants below) and Message is an error message string.

func (ExtractKeySpaceIDError) Error

func (err ExtractKeySpaceIDError) Error() string