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 AddFilteredReplicationUnfriendly(sql string) string
• func AddFilteredReplicationUnfriendlyIfDML(sql string) string
• func AddIfDML(sql string, keyspaceIDs [][]byte) string
• func AddKeyspaceID(sql string, keyspaceID []byte, trailingComments string) string
• func AddKeyspaceIDIfDML(sql string, keyspaceID []byte) string
• func ExtractKeySpaceID(sql string) (keyspaceID []byte, err error)
• type ExtractKeySpaceIDError
  • func (err ExtractKeySpaceIDError) Error() string

Constants

const (
	ExtractKeySpaceIDParseError                 = iota
	ExtractKeySpaceIDReplicationUnfriendlyError = iota
)

Possible values for ExtractKeySpaceIDError.Kind

Functions

func AddFilteredReplicationUnfriendly

func AddFilteredReplicationUnfriendly(sql string) string

AddFilteredReplicationUnfriendly annotates the given 'sql' query as filtered-replication-unfriendly.

func AddFilteredReplicationUnfriendlyIfDML

func AddFilteredReplicationUnfriendlyIfDML(sql string) string

AddFilteredReplicationUnfriendlyIfDML annotates the given 'sql' query as filtered-replication-unfriendly if its a DML statement (filtered-replication should halt if it encounters such an annotation). Does nothing if the statement is not a DML statement.

func AddIfDML

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

AddIfDML annotates 'sql' based on the keyspaceIDs found in 'keyspaceIDs':

If 'sql' is not a DML statement no annotation is added. If 'sql' is a DML statement and contains exactly one element it is used to annotate 'sql'; otherwise 'sql' is annotated as replication-unfriendly.

func AddKeyspaceID

func AddKeyspaceID(sql string, keyspaceID []byte, trailingComments string) string

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

func AddKeyspaceIDIfDML

func AddKeyspaceIDIfDML(sql string, keyspaceID []byte) string

AddKeyspaceIDIfDML returns a copy of 'sql' annotated with the given keyspace id if 'sql' is a DML statement; otherwise, it returns a copy of 'sql'.

func ExtractKeySpaceID

func ExtractKeySpaceID(sql string) (keyspaceID []byte, err error)

ExtractKeySpaceID 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