com.espertech.esper.epl.join.plan

Class NStreamOuterQueryPlanBuilder

java.lang.Object

com.espertech.esper.epl.join.plan.NStreamOuterQueryPlanBuilder

public class NStreamOuterQueryPlanBuilder
extends Object

Builds a query plan for 3 or more streams in a outer join.

Constructor Summary

Constructors

Constructor and Description
NStreamOuterQueryPlanBuilder()

Method Summary

Modifier and Type	Method and Description
protected static QueryPlan	build(QueryGraph queryGraph, OuterJoinDesc[] outerJoinDescList, String[] streamNames, EventType[] typesPerStream, HistoricalViewableDesc historicalViewableDesc, DependencyGraph dependencyGraph, HistoricalStreamIndexList[] historicalStreamIndexLists, ExprEvaluatorContext exprEvaluatorContext, String[][][] indexedStreamsUniqueProps, TableMetadata[] tablesPerStream, EngineImportService engineImportService, boolean isFireAndForget) Build a query plan based on the stream property relationships indicated in queryGraph.
protected static OuterInnerDirectionalGraph	graphOuterJoins(int numStreams, OuterJoinDesc[] outerJoinDescList) Builds a graph of outer joins given the outer join information from the statement.
static String	print(Map<Integer,int[]> streamsJoinedPerStream) Returns textual presentation of stream-substream relationships.
protected static void	recursiveBuild(int streamNum, Stack<Integer> streamCallStack, QueryGraph queryGraph, OuterInnerDirectionalGraph outerInnerGraph, InnerJoinGraph innerJoinGraph, Set<Integer> completedStreams, LinkedHashMap<Integer,int[]> substreamsPerStream, boolean[] requiredPerStream, DependencyGraph dependencyGraph) Recusivly builds a substream-per-stream ordered tree graph using the join information supplied for outer joins and from the query graph (where clause).
protected static void	recursiveBuildInnerJoin(int streamNum, Stack<Integer> streamCallStack, QueryGraph queryGraph, Set<Integer> completedStreams, LinkedHashMap<Integer,int[]> substreamsPerStream, DependencyGraph dependencyGraph) Recusivly builds a substream-per-stream ordered tree graph using the join information supplied for outer joins and from the query graph (where clause).
static void	verifyJoinedPerStream(int rootStream, Map<Integer,int[]> streamsJoinedPerStream) Verifies that the tree-like structure representing which streams join (lookup) into which sub-streams is correct, ie.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NStreamOuterQueryPlanBuilder

public NStreamOuterQueryPlanBuilder()

Method Detail

build

protected static QueryPlan build(QueryGraph queryGraph,
                                 OuterJoinDesc[] outerJoinDescList,
                                 String[] streamNames,
                                 EventType[] typesPerStream,
                                 HistoricalViewableDesc historicalViewableDesc,
                                 DependencyGraph dependencyGraph,
                                 HistoricalStreamIndexList[] historicalStreamIndexLists,
                                 ExprEvaluatorContext exprEvaluatorContext,
                                 String[][][] indexedStreamsUniqueProps,
                                 TableMetadata[] tablesPerStream,
                                 EngineImportService engineImportService,
                                 boolean isFireAndForget)
                          throws ExprValidationException

Build a query plan based on the stream property relationships indicated in queryGraph.

Parameters:

queryGraph - - navigation info between streams

streamNames - - stream names

outerJoinDescList - - descriptors for all outer joins

typesPerStream - - event types for each stream

dependencyGraph - - dependencies between historical streams

historicalStreamIndexLists - - index management, populated for the query plan

exprEvaluatorContext - context for expression evaluation

historicalViewableDesc - historicals

indexedStreamsUniqueProps - unique props

tablesPerStream - tables

isFireAndForget - fire-and-forget flag

engineImportService - engine imports

Returns:

query plan

Throws:

ExprValidationException - if the query planning failed

recursiveBuild

protected static void recursiveBuild(int streamNum,
                                     Stack<Integer> streamCallStack,
                                     QueryGraph queryGraph,
                                     OuterInnerDirectionalGraph outerInnerGraph,
                                     InnerJoinGraph innerJoinGraph,
                                     Set<Integer> completedStreams,
                                     LinkedHashMap<Integer,int[]> substreamsPerStream,
                                     boolean[] requiredPerStream,
                                     DependencyGraph dependencyGraph)
                              throws ExprValidationException

Recusivly builds a substream-per-stream ordered tree graph using the join information supplied for outer joins and from the query graph (where clause).

Required streams are considered first and their lookup is placed first in the list to gain performance.

Parameters:

streamNum - is the root stream number that supplies the incoming event to build the tree for

queryGraph - contains where-clause stream relationship info

outerInnerGraph - contains the outer join stream relationship info

completedStreams - is a temporary holder for streams already considered

substreamsPerStream - is the ordered, tree-like structure to be filled

requiredPerStream - indicates which streams are required and which are optional

streamCallStack - the query plan call stack of streams available via cursor

dependencyGraph - - dependencies between historical streams

innerJoinGraph - inner join graph

Throws:

ExprValidationException - if the query planning failed

recursiveBuildInnerJoin

protected static void recursiveBuildInnerJoin(int streamNum,
                                              Stack<Integer> streamCallStack,
                                              QueryGraph queryGraph,
                                              Set<Integer> completedStreams,
                                              LinkedHashMap<Integer,int[]> substreamsPerStream,
                                              DependencyGraph dependencyGraph)
                                       throws ExprValidationException

Recusivly builds a substream-per-stream ordered tree graph using the join information supplied for outer joins and from the query graph (where clause).

Required streams are considered first and their lookup is placed first in the list to gain performance.

Parameters:

streamNum - is the root stream number that supplies the incoming event to build the tree for

queryGraph - contains where-clause stream relationship info

completedStreams - is a temporary holder for streams already considered

substreamsPerStream - is the ordered, tree-like structure to be filled

streamCallStack - the query plan call stack of streams available via cursor

dependencyGraph - - dependencies between historical streams

Throws:

ExprValidationException - if the query planning failed

graphOuterJoins

protected static OuterInnerDirectionalGraph graphOuterJoins(int numStreams,
                                                            OuterJoinDesc[] outerJoinDescList)

Builds a graph of outer joins given the outer join information from the statement. Eliminates right and left joins and full joins by placing the information in a graph object.

Parameters:

numStreams - - is the number of streams

outerJoinDescList - - list of outer join stream numbers and property names

Returns:

graph object

verifyJoinedPerStream

public static void verifyJoinedPerStream(int rootStream,
                                         Map<Integer,int[]> streamsJoinedPerStream)

Verifies that the tree-like structure representing which streams join (lookup) into which sub-streams is correct, ie. all streams are included and none are listed twice.

Parameters:

rootStream - is the stream supplying the incoming event

streamsJoinedPerStream - is keyed by the from-stream number and contains as values all stream numbers of lookup into to-streams.

print

public static String print(Map<Integer,int[]> streamsJoinedPerStream)

Returns textual presentation of stream-substream relationships.

Parameters:

streamsJoinedPerStream - is the tree-like structure of stream-substream

Returns:

textual presentation