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[Fix](Join) Fix the bug of outer join function under vectorization #9954

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@EmmyMiao87 EmmyMiao87 commented Jun 4, 2022

Proposed changes

Closed #7901

Problem Summary

This pr mainly fixes the following problems:

  1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the tupleisnull function is inconsistent with the row storage. Currently the vectorized tupleisnull will be calculated in the HashJoinNode.computeOutputTuple() function.
  2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

About 1:

For example:

select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1

At this time, the nullable property of column k1 in the tmp inline view should be true.

In the vectorized code, the virtual tableRef of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the correctness of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the TupleIsNull function in outputsmp to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

About 2

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Checklist(Required)

  1. Does it affect the original behavior: (Yes/No/I Don't know)
  2. Has unit tests been added: (Yes/No/No Need)
  3. Has document been added or modified: (Yes/No/No Need)
  4. Does it need to update dependencies: (Yes/No)
  5. Are there any changes that cannot be rolled back: (Yes/No)

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

@github-actions github-actions bot added the area/planner Issues or PRs related to the query planner label Jun 4, 2022
@morningman morningman added this to the v1.1 milestone Jun 4, 2022
@morningman morningman added the dev/1.0.1-deprecated should be merged into dev-1.0.1 branch label Jun 4, 2022
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Could you add some ut for this?

@@ -410,6 +410,10 @@ struct THashJoinNode {

// hash output column
6: optional list<Types.TSlotId> hash_output_slot_ids

7: optional list<Exprs.TExpr> srcExprList
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use src_expr_list

@EmmyMiao87 EmmyMiao87 force-pushed the outerjoin_tuple branch 3 times, most recently from a184356 to 12ce8c4 Compare June 20, 2022 09:49
@@ -893,7 +893,6 @@ private void filterDeletedRows(Analyzer analyzer) throws AnalysisException {
SlotRef deleteSignSlot = new SlotRef(desc.getAliasAsName(), Column.DELETE_SIGN);
deleteSignSlot.analyze(analyzer);
deleteSignSlot.getDesc().setIsMaterialized(true);
deleteSignSlot.getDesc().setIsNullable(analyzer.isOuterMaterializedJoined(desc.getId()));
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we also need to remove setIsNullable in Analyzer#registerColumnRef


7: optional list<Exprs.TExpr> srcExprList

8: optional Types.TTupleId voutput_tuple_id
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move it to TPlanNode

@EmmyMiao87 EmmyMiao87 force-pushed the outerjoin_tuple branch 2 times, most recently from 5d367fb to 4bf85f1 Compare June 21, 2022 07:59
@morningman morningman closed this Jun 22, 2022
@morningman morningman removed the dev/1.0.1-deprecated should be merged into dev-1.0.1 branch label Jun 22, 2022
@EmmyMiao87 EmmyMiao87 reopened this Jun 23, 2022
@EmmyMiao87 EmmyMiao87 force-pushed the outerjoin_tuple branch 2 times, most recently from cf8fb62 to 1c4f4b4 Compare June 24, 2022 04:59
@EmmyMiao87 EmmyMiao87 changed the title [Enhancement](Join) Construct output tuple in join node [Fix](Join) Solve the problem of incorrectly evaluating column null properties when combining inline view and outer join. Jun 24, 2022
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LGTM

@morningman morningman added the dev/1.0.1-deprecated should be merged into dev-1.0.1 branch label Jun 24, 2022
@github-actions github-actions bot added the approved Indicates a PR has been approved by one committer. label Jun 24, 2022
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PR approved by at least one committer and no changes requested.

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PR approved by anyone and no changes requested.

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hold for a second, there is still some problem

@github-actions github-actions bot removed the approved Indicates a PR has been approved by one committer. label Jun 26, 2022
@EmmyMiao87 EmmyMiao87 changed the title [Fix](Join) Solve the problem of incorrectly evaluating column null properties when combining inline view and outer join. [Fix](Join) Fix the bug of outer join function under vectorization Jun 27, 2022
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EmmyMiao87 commented Jun 27, 2022

The contents of this pr are merged into the new pr #10437 and submitted together

@EmmyMiao87 EmmyMiao87 closed this Jun 27, 2022
@morningman morningman removed the dev/1.0.1-deprecated should be merged into dev-1.0.1 branch label Jun 29, 2022
EmmyMiao87 added a commit to EmmyMiao87/incubator-doris that referenced this pull request Jul 19, 2022
Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow
morningman pushed a commit to morningman/doris that referenced this pull request Jul 21, 2022
Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow
morningman pushed a commit to morningman/doris that referenced this pull request Jul 21, 2022
Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow
morningman pushed a commit to morningman/doris that referenced this pull request Jul 21, 2022
Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow
morningman pushed a commit to morningman/doris that referenced this pull request Jul 21, 2022
Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow
morningman added a commit that referenced this pull request Jul 21, 2022
)

Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization #9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow

Co-authored-by: EmmyMiao87 <522274284@qq.com>
miswujian pushed a commit to miswujian/doris that referenced this pull request Jul 28, 2022
…che#11068)

Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow

Co-authored-by: EmmyMiao87 <522274284@qq.com>
whutpencil pushed a commit to whutpencil/incubator-doris that referenced this pull request Jul 29, 2022
…che#11068)

Hash join node adds three new attributes.
The following will take an SQL as an example to illustrate the meaning of these three attributes

```
select t1. a from t1 left join t2 on t1. a=t2. b;
```
1. vOutputTupleDesc:Tuple2(a'')

2. vIntermediateTupleDescList: Tuple1(a', b'<nullable>)

2. vSrcToOutputSMap: <Tuple1(a'), Tuple2(a'')>

The slot in intermediatetuple corresponds to the slot in output tuple one by one through the expr calculation of the left child in vsrctooutputsmap.

This code mainly merges the contents of two PRs:
1.  [fix](vectorized) Support outer join for vectorized exec engine (apache#10323)
2. [Fix](Join) Fix the bug of outer join function under vectorization apache#9954

The following is the specific description of the first PR
In a vectorized scenario, the query plan will generate a new tuple for the join node.
This tuple mainly describes the output schema of the join node.
Adding this tuple mainly solves the problem that the input schema of the join node is different from the output schema.
For example:
1. The case where the null side column caused by outer join is converted to nullable.
2. The projection of the outer tuple.

The following is the specific description of the second PR
This pr mainly fixes the following problems:
1. Solve the query combined with inline view and outer join. After adding a tuple to the join operator, the position of the `tupleisnull` function is inconsistent with the row storage. Currently the vectorized `tupleisnull` will be calculated in the HashJoinNode.computeOutputTuple() function.
2. Column nullable property error problem. At present, once the outer join occurs, the column on the null-side side will be planned to be nullable in the semantic parsing stage.

For example:
```
select * from (select a as k1 from test) tmp right join b on tmp.k1=b.k1
```
At this time, the nullable property of column k1 in the `tmp` inline view should be true.

In the vectorized code, the virtual `tableRef` of tmp will be used in constructing the output tuple of HashJoinNode (specifically, the function HashJoinNode.computeOutputTuple()). So the **correctness** of the column nullable property of this tableRef is very important.
In the above case, since the tmp table needs to perform a right join with the b table, as a null-side tmp side, it is necessary to change the column attributes involved in the tmp table to nullable.

In non-vectorized code, since the virtual tableRef tmp is not used at all, it uses the `TupleIsNull` function in `outputsmp` to ensure data correctness.
That is to say, the a column of the original table test is still non-null, and it does not affect the correctness of the result.

The vectorized nullable attribute requirements are very strict.
Outer join will change the nullable attribute of the join column, thereby changing the nullable attribute of the column in the upper operator layer by layer.
Since FE has no mechanism to modify the nullable attribute in the upper operator tuple layer by layer after the analyzer.
So at present, we can only preset the attributes before the lower join as nullable in the analyzer stage in advance, so as to avoid the problem.
(At the same time, be also wrote some evasive code in order to deal with the problem of null to non-null.)

Co-authored-by: EmmyMiao87
Co-authored-by: HappenLee
Co-authored-by: morrySnow

Co-authored-by: EmmyMiao87 <522274284@qq.com>
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[Feature] [Vectorized] Some Join opt in vec exec engine
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