[This topic is pre-release documentation and is subject to change in future releases. Blank topics are included as placeholders.]
2 Stream query strategy/execution tree
(stream 0) Lookup in stream 1
(stream 1) Lookup in stream 0
------ Example 1 a 3 table join
" where streamA.id = streamB.id " +
" and streamB.id = streamC.id";
=> Index propery names for each stream
for stream 0 to 4 = "id"
=> join order, ie.
for stream 0 = {1, 2}
for stream 1 = {factor [0,2]}
for stream 2 = {1, 0}
=> IndexKeyGen optionalIndexKeyGen, created by nested query plan nodes
3 Stream query strategy
(stream 0) Nested iteration
Lookup in stream 1 Lookup in stream 2
(stream 1) Factor
Lookup in stream 0 Lookup in stream 2
(stream 2) Nested iteration
Lookup in stream 1 Lookup in stream 0
------ Example 2 a 4 table join
" where streamA.id = streamB.id " +
" and streamB.id = streamC.id";
" and streamC.id = streamD.id";
=> join order, ie.
for stream 0 = {1, 2, 3}
for stream 1 = {factor [0,2], use 2 for 3}
for stream 2 = {factor [1,3], use 1 for 0}
for stream 3 = {2, 1, 0}
concepts... nested iteration, inner loop
select * from s1, s2, s3, s4 where s1.id=s2.id and s2.id=s3.id and s3.id=s4.id
(stream 0) Nested iteration
Lookup in stream 1 Lookup in stream 2 Lookup in stream 3
(stream 1) Factor
lookup in stream 0 Nested iteration
Lookup in stream 2 Lookup in stream 3
(stream 2) Factor
lookup in stream 3 Nested iteration
Lookup in stream 1 Lookup in stream 0
(stream 3) Nested iteration
Lookup in stream 2 Lookup in stream 1 Lookup in stream 0
------ Example 4 a 4 table join, orphan table
" where streamA.id = streamB.id " +
" and streamB.id = streamC.id"; (no table D join criteria)
------ Example 5 a 3 table join with 2 indexes for stream B
" where streamA.A1 = streamB.B1 " +
" and streamB.B2 = streamC.C1"; (no table D join criteria)
Builds a query plan for 3 or more streams in a join.
Namespace: net.esper.eql.join.plan
Assembly:
NEsper (in NEsper.dll)
Syntax
Visual Basic (Declaration) |
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Public Class NStreamQueryPlanBuilder |
C# |
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public class NStreamQueryPlanBuilder |
Visual C++ |
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public ref class NStreamQueryPlanBuilder |
Inheritance Hierarchy