[SPARK-23406][SS] Enable stream-stream self-joins for branch-2.3 #20765
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## What changes were proposed in this pull request?
Solved two bugs to enable stream-stream self joins.
### Incorrect analysis due to missing MultiInstanceRelation trait
Streaming leaf nodes did not extend MultiInstanceRelation, which is necessary for the catalyst analyzer to convert the self-join logical plan DAG into a tree (by creating new instances of the leaf relations). This was causing the error `Failure when resolving conflicting references in Join:` (see JIRA for details).
### Incorrect attribute rewrite when splicing batch plans in MicroBatchExecution
When splicing the source's batch plan into the streaming plan (by replacing the StreamingExecutionPlan), we were rewriting the attribute reference in the streaming plan with the new attribute references from the batch plan. This was incorrectly handling the scenario when multiple StreamingExecutionRelation point to the same source, and therefore eventually point to the same batch plan returned by the source. Here is an example query, and its corresponding plan transformations.
```
val df = input.toDF
val join =
df.select('value % 5 as "key", 'value).join(
df.select('value % 5 as "key", 'value), "key")
```
Streaming logical plan before splicing the batch plan
```
Project [key#6, value#1, value#12]
+- Join Inner, (key#6 = key#9)
:- Project [(value#1 % 5) AS key#6, value#1]
: +- StreamingExecutionRelation Memory[#1], value#1
+- Project [(value#12 % 5) AS key#9, value#12]
+- StreamingExecutionRelation Memory[#1], value#12 // two different leaves pointing to same source
```
Batch logical plan after splicing the batch plan and before rewriting
```
Project [key#6, value#1, value#12]
+- Join Inner, (key#6 = key#9)
:- Project [(value#1 % 5) AS key#6, value#1]
: +- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#1
+- Project [(value#12 % 5) AS key#9, value#12]
+- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#12
```
Batch logical plan after rewriting the attributes. Specifically, for spliced, the new output attributes (value#66) replace the earlier output attributes (value#12, and value#1, one for each StreamingExecutionRelation).
```
Project [key#6, value#66, value#66] // both value#1 and value#12 replaces by value#66
+- Join Inner, (key#6 = key#9)
:- Project [(value#66 % 5) AS key#6, value#66]
: +- LocalRelation [value#66]
+- Project [(value#66 % 5) AS key#9, value#66]
+- LocalRelation [value#66]
```
This causes the optimizer to eliminate value#66 from one side of the join.
```
Project [key#6, value#66, value#66]
+- Join Inner, (key#6 = key#9)
:- Project [(value#66 % 5) AS key#6, value#66]
: +- LocalRelation [value#66]
+- Project [(value#66 % 5) AS key#9] // this does not generate value, incorrect join results
+- LocalRelation [value#66]
```
**Solution**: Instead of rewriting attributes, use a Project to introduce aliases between the output attribute references and the new reference generated by the spliced plans. The analyzer and optimizer will take care of the rest.
```
Project [key#6, value#1, value#12]
+- Join Inner, (key#6 = key#9)
:- Project [(value#1 % 5) AS key#6, value#1]
: +- Project [value#66 AS value#1] // solution: project with aliases
: +- LocalRelation [value#66]
+- Project [(value#12 % 5) AS key#9, value#12]
+- Project [value#66 AS value#12] // solution: project with aliases
+- LocalRelation [value#66]
```
## How was this patch tested?
New unit test
Author: Tathagata Das <tathagata.das1565@gmail.com>
Closes apache#20598 from tdas/SPARK-23406.
|
Test build #88067 has finished for PR 20765 at commit
|
asfgit
pushed a commit
that referenced
this pull request
Mar 8, 2018
This is a backport of #20598. ## What changes were proposed in this pull request? Solved two bugs to enable stream-stream self joins. ### Incorrect analysis due to missing MultiInstanceRelation trait Streaming leaf nodes did not extend MultiInstanceRelation, which is necessary for the catalyst analyzer to convert the self-join logical plan DAG into a tree (by creating new instances of the leaf relations). This was causing the error `Failure when resolving conflicting references in Join:` (see JIRA for details). ### Incorrect attribute rewrite when splicing batch plans in MicroBatchExecution When splicing the source's batch plan into the streaming plan (by replacing the StreamingExecutionPlan), we were rewriting the attribute reference in the streaming plan with the new attribute references from the batch plan. This was incorrectly handling the scenario when multiple StreamingExecutionRelation point to the same source, and therefore eventually point to the same batch plan returned by the source. Here is an example query, and its corresponding plan transformations. ``` val df = input.toDF val join = df.select('value % 5 as "key", 'value).join( df.select('value % 5 as "key", 'value), "key") ``` Streaming logical plan before splicing the batch plan ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- StreamingExecutionRelation Memory[#1], value#1 +- Project [(value#12 % 5) AS key#9, value#12] +- StreamingExecutionRelation Memory[#1], value#12 // two different leaves pointing to same source ``` Batch logical plan after splicing the batch plan and before rewriting ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#1 +- Project [(value#12 % 5) AS key#9, value#12] +- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#12 ``` Batch logical plan after rewriting the attributes. Specifically, for spliced, the new output attributes (value#66) replace the earlier output attributes (value#12, and value#1, one for each StreamingExecutionRelation). ``` Project [key#6, value#66, value#66] // both value#1 and value#12 replaces by value#66 +- Join Inner, (key#6 = key#9) :- Project [(value#66 % 5) AS key#6, value#66] : +- LocalRelation [value#66] +- Project [(value#66 % 5) AS key#9, value#66] +- LocalRelation [value#66] ``` This causes the optimizer to eliminate value#66 from one side of the join. ``` Project [key#6, value#66, value#66] +- Join Inner, (key#6 = key#9) :- Project [(value#66 % 5) AS key#6, value#66] : +- LocalRelation [value#66] +- Project [(value#66 % 5) AS key#9] // this does not generate value, incorrect join results +- LocalRelation [value#66] ``` **Solution**: Instead of rewriting attributes, use a Project to introduce aliases between the output attribute references and the new reference generated by the spliced plans. The analyzer and optimizer will take care of the rest. ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- Project [value#66 AS value#1] // solution: project with aliases : +- LocalRelation [value#66] +- Project [(value#12 % 5) AS key#9, value#12] +- Project [value#66 AS value#12] // solution: project with aliases +- LocalRelation [value#66] ``` ## How was this patch tested? New unit test Author: Tathagata Das <tathagata.das1565@gmail.com> Closes #20765 from tdas/SPARK-23406-2.3.
peter-toth
pushed a commit
to peter-toth/spark
that referenced
this pull request
Oct 6, 2018
This is a backport of apache#20598. ## What changes were proposed in this pull request? Solved two bugs to enable stream-stream self joins. ### Incorrect analysis due to missing MultiInstanceRelation trait Streaming leaf nodes did not extend MultiInstanceRelation, which is necessary for the catalyst analyzer to convert the self-join logical plan DAG into a tree (by creating new instances of the leaf relations). This was causing the error `Failure when resolving conflicting references in Join:` (see JIRA for details). ### Incorrect attribute rewrite when splicing batch plans in MicroBatchExecution When splicing the source's batch plan into the streaming plan (by replacing the StreamingExecutionPlan), we were rewriting the attribute reference in the streaming plan with the new attribute references from the batch plan. This was incorrectly handling the scenario when multiple StreamingExecutionRelation point to the same source, and therefore eventually point to the same batch plan returned by the source. Here is an example query, and its corresponding plan transformations. ``` val df = input.toDF val join = df.select('value % 5 as "key", 'value).join( df.select('value % 5 as "key", 'value), "key") ``` Streaming logical plan before splicing the batch plan ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- StreamingExecutionRelation Memory[#1], value#1 +- Project [(value#12 % 5) AS key#9, value#12] +- StreamingExecutionRelation Memory[#1], value#12 // two different leaves pointing to same source ``` Batch logical plan after splicing the batch plan and before rewriting ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#1 +- Project [(value#12 % 5) AS key#9, value#12] +- LocalRelation [value#66] // replaces StreamingExecutionRelation Memory[#1], value#12 ``` Batch logical plan after rewriting the attributes. Specifically, for spliced, the new output attributes (value#66) replace the earlier output attributes (value#12, and value#1, one for each StreamingExecutionRelation). ``` Project [key#6, value#66, value#66] // both value#1 and value#12 replaces by value#66 +- Join Inner, (key#6 = key#9) :- Project [(value#66 % 5) AS key#6, value#66] : +- LocalRelation [value#66] +- Project [(value#66 % 5) AS key#9, value#66] +- LocalRelation [value#66] ``` This causes the optimizer to eliminate value#66 from one side of the join. ``` Project [key#6, value#66, value#66] +- Join Inner, (key#6 = key#9) :- Project [(value#66 % 5) AS key#6, value#66] : +- LocalRelation [value#66] +- Project [(value#66 % 5) AS key#9] // this does not generate value, incorrect join results +- LocalRelation [value#66] ``` **Solution**: Instead of rewriting attributes, use a Project to introduce aliases between the output attribute references and the new reference generated by the spliced plans. The analyzer and optimizer will take care of the rest. ``` Project [key#6, value#1, value#12] +- Join Inner, (key#6 = key#9) :- Project [(value#1 % 5) AS key#6, value#1] : +- Project [value#66 AS value#1] // solution: project with aliases : +- LocalRelation [value#66] +- Project [(value#12 % 5) AS key#9, value#12] +- Project [value#66 AS value#12] // solution: project with aliases +- LocalRelation [value#66] ``` ## How was this patch tested? New unit test Author: Tathagata Das <tathagata.das1565@gmail.com> Closes apache#20765 from tdas/SPARK-23406-2.3.
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This is a backport of #20598.
What changes were proposed in this pull request?
Solved two bugs to enable stream-stream self joins.
Incorrect analysis due to missing MultiInstanceRelation trait
Streaming leaf nodes did not extend MultiInstanceRelation, which is necessary for the catalyst analyzer to convert the self-join logical plan DAG into a tree (by creating new instances of the leaf relations). This was causing the error
Failure when resolving conflicting references in Join:(see JIRA for details).Incorrect attribute rewrite when splicing batch plans in MicroBatchExecution
When splicing the source's batch plan into the streaming plan (by replacing the StreamingExecutionPlan), we were rewriting the attribute reference in the streaming plan with the new attribute references from the batch plan. This was incorrectly handling the scenario when multiple StreamingExecutionRelation point to the same source, and therefore eventually point to the same batch plan returned by the source. Here is an example query, and its corresponding plan transformations.
Streaming logical plan before splicing the batch plan
Batch logical plan after splicing the batch plan and before rewriting
Batch logical plan after rewriting the attributes. Specifically, for spliced, the new output attributes (value#66) replace the earlier output attributes (value#12, and value#1, one for each StreamingExecutionRelation).
This causes the optimizer to eliminate value#66 from one side of the join.
Solution: Instead of rewriting attributes, use a Project to introduce aliases between the output attribute references and the new reference generated by the spliced plans. The analyzer and optimizer will take care of the rest.
How was this patch tested?
New unit test