xzj7019 commented on code in PR #1597:
URL: https://github.com/apache/doris-website/pull/1597#discussion_r1897213886
##########
docs/query-acceleration/tuning/tuning-plan/adjusting-join-shuffle.md:
##########
@@ -1,127 +1,95 @@
----
-{
- "title": "Adjusting Join Shuffle with Hint",
- "language": "en"
-}
----
-
-<!--
-Licensed to the Apache Software Foundation (ASF) under one
-or more contributor license agreements. See the NOTICE file
-distributed with this work for additional information
-regarding copyright ownership. The ASF licenses this file
-to you under the Apache License, Version 2.0 (the
-"License"); you may not use this file except in compliance
-with the License. You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing,
-software distributed under the License is distributed on an
-"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-KIND, either express or implied. See the License for the
-specific language governing permissions and limitations
-under the License.
--->
-
-## Principle
-
-Doris supports the use of hints to adjust the type of data shuffle in Join
operations, thereby optimizing query performance. This section will introduce
in detail how to use hints in Doris to specify the type of Join shuffle.
-
-Currently, Doris is limited to specifying the Distribute Type for the right
table in a Join and provides only two types to choose from: `[shuffle]` and
`[broadcast]`. The Distribute Type needs to be placed before the right table in
the Join, using square brackets `[]`.
-
-
-Examples are as follows:
-
-```sql
-SELECT COUNT(*) FROM t2 JOIN [broadcast] t1 ON t1.c1 = t2.c2;
-SELECT COUNT(*) FROM t2 JOIN [shuffle] t1 ON t1.c1 = t2.c2;
-SELECT /*+ ordered */ COUNT(*) FROM t2 JOIN [broadcast] t1 ON t1.c1 = t2.c2;
-SELECT /*+ ordered */ COUNT(*) FROM t2 JOIN [shuffle] t1 ON t1.c1 = t2.c2;
-```
-
-
-When using hints, please note the following:
-
-1. If Doris encounters a DistributeHint that cannot correctly generate an
execution plan, it will not display the hint but will make it effective
according to the "best effort" principle. Ultimately, the distribute method
displayed by EXPLAIN shall be deemed as final.
-
-2. In the current version, DistributeHint does not support mixing with
LEADING, and the hint will only take effect when the table specified by
distribute is on the right side of the Join.
-
-3. It is recommended to mix DistributeHint with ORDERED. First, use ORDERED to
fix the Join order, and then specify the expected distribute method in the
corresponding Join.
-
-## Use Case
-
-Next, we will demonstrate the use of hints through the same example:
-
-**1. Before Using Hint:**
-
-```sql
-EXPLAIN SHAPE PLAN SELECT COUNT(*) FROM t1 JOIN t2 ON t1.c1 = t2.c2;
-```
-
-Result:
-
-```sql
-+----------------------------------------------------------------------------------+
-| Explain String (Nereids Planner)
|
-+----------------------------------------------------------------------------------+
-| PhysicalResultSink
|
-| --hashAgg [GLOBAL]
|
-| ----PhysicalDistribute [DistributionSpecGather]
|
-| ------hashAgg [LOCAL]
|
-| --------PhysicalProject
|
-| ----------hashJoin [INNER_JOIN] hashCondition=((t1.c1 = t2.c2))
otherCondition=()|
-| ------------PhysicalProject
|
-| --------------PhysicalOlapScan [t1]
|
-| ------------PhysicalDistribute [DistributionSpecHash]
|
-| --------------PhysicalProject
|
-| ----------------PhysicalOlapScan [t2]
|
-+----------------------------------------------------------------------------------+
-```
-
-**2. After Using Hint:**
-
-```sql
-EXPLAIN SHAPE PLAN SELECT /*+ ordered */ COUNT(*) FROM t2 JOIN [broadcast] t1
ON t1.c1 = t2.c2;
-```
-
-Result:
-
-```sql
-+----------------------------------------------------------------------------------+
-| Explain String (Nereids Planner)
|
-+----------------------------------------------------------------------------------+
-| PhysicalResultSink
|
-| --hashAgg [GLOBAL]
|
-| ----PhysicalDistribute [DistributionSpecGather]
|
-| ------hashAgg [LOCAL]
|
-| --------PhysicalProject
|
-| ----------hashJoin [INNER_JOIN] hashCondition=((t1.c1 = t2.c2))
otherCondition=()|
-| ------------PhysicalProject
|
-| --------------PhysicalOlapScan [t2]
|
-| ------------PhysicalDistribute [DistributionSpecReplicated]
|
-| --------------PhysicalProject
|
-| ----------------PhysicalOlapScan [t1]
|
-|
|
-| Hint log:
|
-| Used: ORDERED
|
-| UnUsed:
|
-| SyntaxError:
|
-+----------------------------------------------------------------------------------+
-```
-
-In the EXPLAIN results, you can see the relevant information for the
distribute operator:
-
-1. `DistributionSpecReplicated` indicates that the corresponding data is
replicated to all BE nodes.
-
-2. `DistributionSpecGather` indicates that the data is gathered to the FE node.
-
-3. `DistributionSpecHash` indicates that the data is scattered to different BE
nodes according to a specific HashKey and algorithm.
-
-## Summary
-
-By reasonably using DistributeHint, you can optimize the Shuffle method for
Join operations and enhance query performance. In practice, it is recommended
to first analyze the query execution plan using EXPLAIN and then select the
appropriate Shuffle type based on the actual situation. When using it, please
pay attention to the following points:
-
-1. If a DistributeHint fails to correctly generate an execution plan, Doris
will not display the Hint but will make it effective based on the principle of
"best effort". Ultimately, the Distribute method displayed by EXPLAIN prevails.
-2. In the current version, DistributeHint temporarily does not support mixing
with LEADING, and the Hint will only take effect when the table specified by
Distribute is located on the right side of the Join.
-3. It is recommended to mix DistributeHint with ORDERED. First, use ORDERED to
fix the Join order, and then specify the expected Distribute method for the
corresponding Join.
\ No newline at end of file
+{
+ "title": "Adjusting Join Shuffle Mode with Hint",
+ "language": "en"
+}
+---
+
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+## Overview
+
+Doris supports the use of hints to adjust the type of data shuffle in Join
operations, thereby optimizing query performance. This section provides
detailed instructions on how to specify the Join Shuffle type in Doris using
hints.
+
+Currently, Doris supports two independent [Distribute
Hint](../../../query-acceleration/hints/distribute-hint.md), `[shuffle]` and
`[broadcast]`, to specify the Distribute Type for the right table in a Join.
The Distribute Type should be placed before the right table in the Join,
enclosed in square brackets `[]`. Additionally, Doris can specify the shuffle
mode by using the Leading Hint in conjunction with the Distribute Hint (for
more details, refer to [使用 Leading Hint 控制 Join
顺序](reordering-join-with-leading-hint.md)).
Review Comment:
[使用 Leading Hint 控制 Join 顺序] => english
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