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#135 update spark version r37 #141

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merged 1 commit into from
Jul 2, 2020

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@yugan95 yugan95 commented Jul 2, 2020

What changes were proposed in this pull request?

(Please fill in changes proposed in this fix)

How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)
(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Please review http://spark.apache.org/contributing.html before opening a pull request.

@yugan95 yugan95 merged commit a2ce93f into Kyligence:kyspark-2.4.1.x-4.x Jul 2, 2020
@yugan95 yugan95 deleted the jackson-r37 branch July 2, 2020 07:59
zheniantoushipashi pushed a commit that referenced this pull request Jul 11, 2020
7mming7 pushed a commit that referenced this pull request Nov 4, 2020
### What changes were proposed in this pull request?

Currently `BroadcastHashJoinExec` and `ShuffledHashJoinExec` do not preserve children output ordering information (inherit from `SparkPlan.outputOrdering`, which is Nil). This can add unnecessary sort in complex queries involved multiple joins.

Example:

```
withSQLConf(
      SQLConf.AUTO_BROADCASTJOIN_THRESHOLD.key -> "50") {
      val df1 = spark.range(100).select($"id".as("k1"))
      val df2 = spark.range(100).select($"id".as("k2"))
      val df3 = spark.range(3).select($"id".as("k3"))
      val df4 = spark.range(100).select($"id".as("k4"))
      val plan = df1.join(df2, $"k1" === $"k2")
        .join(df3, $"k1" === $"k3")
        .join(df4, $"k1" === $"k4")
        .queryExecution
        .executedPlan
}
```

Current physical plan (extra sort on `k1` before top sort merge join):

```
*(9) SortMergeJoin [k1#220L], [k4#232L], Inner
:- *(6) Sort [k1#220L ASC NULLS FIRST], false, 0
:  +- *(6) BroadcastHashJoin [k1#220L], [k3#228L], Inner, BuildRight
:     :- *(6) SortMergeJoin [k1#220L], [k2#224L], Inner
:     :  :- *(2) Sort [k1#220L ASC NULLS FIRST], false, 0
:     :  :  +- Exchange hashpartitioning(k1#220L, 5), true, [id=#128]
:     :  :     +- *(1) Project [id#218L AS k1#220L]
:     :  :        +- *(1) Range (0, 100, step=1, splits=2)
:     :  +- *(4) Sort [k2#224L ASC NULLS FIRST], false, 0
:     :     +- Exchange hashpartitioning(k2#224L, 5), true, [id=#134]
:     :        +- *(3) Project [id#222L AS k2#224L]
:     :           +- *(3) Range (0, 100, step=1, splits=2)
:     +- BroadcastExchange HashedRelationBroadcastMode(List(input[0, bigint, false])), [id=#141]
:        +- *(5) Project [id#226L AS k3#228L]
:           +- *(5) Range (0, 3, step=1, splits=2)
+- *(8) Sort [k4#232L ASC NULLS FIRST], false, 0
   +- Exchange hashpartitioning(k4#232L, 5), true, [id=#148]
      +- *(7) Project [id#230L AS k4#232L]
         +- *(7) Range (0, 100, step=1, splits=2)
```

Ideal physical plan (no extra sort on `k1` before top sort merge join):

```
*(9) SortMergeJoin [k1#220L], [k4#232L], Inner
:- *(6) BroadcastHashJoin [k1#220L], [k3#228L], Inner, BuildRight
:  :- *(6) SortMergeJoin [k1#220L], [k2#224L], Inner
:  :  :- *(2) Sort [k1#220L ASC NULLS FIRST], false, 0
:  :  :  +- Exchange hashpartitioning(k1#220L, 5), true, [id=#127]
:  :  :     +- *(1) Project [id#218L AS k1#220L]
:  :  :        +- *(1) Range (0, 100, step=1, splits=2)
:  :  +- *(4) Sort [k2#224L ASC NULLS FIRST], false, 0
:  :     +- Exchange hashpartitioning(k2#224L, 5), true, [id=#133]
:  :        +- *(3) Project [id#222L AS k2#224L]
:  :           +- *(3) Range (0, 100, step=1, splits=2)
:  +- BroadcastExchange HashedRelationBroadcastMode(List(input[0, bigint, false])), [id=#140]
:     +- *(5) Project [id#226L AS k3#228L]
:        +- *(5) Range (0, 3, step=1, splits=2)
+- *(8) Sort [k4#232L ASC NULLS FIRST], false, 0
   +- Exchange hashpartitioning(k4#232L, 5), true, [id=#146]
      +- *(7) Project [id#230L AS k4#232L]
         +- *(7) Range (0, 100, step=1, splits=2)
```

### Why are the changes needed?

To avoid unnecessary sort in query, and it has most impact when users read sorted bucketed table.
Though the unnecessary sort is operating on already sorted data, it would have obvious negative impact on IO and query run time if the data is large and external sorting happens.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Added unit test in `JoinSuite`.

Closes apache#29181 from c21/ordering.

Authored-by: Cheng Su <[email protected]>
Signed-off-by: Wenchen Fan <[email protected]>
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3 participants