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[fix](Nereids) fix hint doc #2326

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2 changes: 1 addition & 1 deletion docs/query-acceleration/hints/distribute-hint.md
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Original file line number Diff line number Diff line change
Expand Up @@ -105,7 +105,7 @@ explain shape plan
from
(
select
/*+ leading(orders shuffle {lineitem shuffle part} shuffle {supplier broadcast nation} shuffle partsupp) */
/*+ leading(orders [shuffle] (lineitem [shuffle] part) [shuffle] (supplier [broadcast] nation) [shuffle] partsupp) */
n_name as nation,
extract(year from o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
Expand Down
22 changes: 11 additions & 11 deletions docs/query-acceleration/hints/leading-hint.md
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Original file line number Diff line number Diff line change
Expand Up @@ -99,7 +99,7 @@ When Leading Hint is not effective, the normal process will be used to generate

2. At the same time, curly braces can be used to specify the shape of the Join tree:
```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on c1 = c2 join t3 on c2=c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 join t2 on c1 = c2 join t3 on c2=c3;
+----------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+----------------------------------------------------------------------------------+
Expand All @@ -115,7 +115,7 @@ When Leading Hint is not effective, the normal process will be used to generate
| --------------PhysicalOlapScan[t3] |
| |
| Hint log: |
| Used: leading(t1 { t2 t3 }) |
| Used: leading(t1 ( t2 t3 )) |
| UnUsed: |
| SyntaxError: |
+----------------------------------------------------------------------------------+
Expand Down Expand Up @@ -262,7 +262,7 @@ When Leading Hint is not effective, the normal process will be used to generate
When you need to make the shape of the plan a right-deep tree, Bushy tree, or zig-zag tree, you only need to add curly braces to limit the shape of the plan, without the need to use swap like Oracle to adjust step by step from the left-deep tree.

```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3;
+-----------------------------------------------+
| Explain String |
+-----------------------------------------------+
Expand All @@ -277,7 +277,7 @@ When Leading Hint is not effective, the normal process will be used to generate
| ------------PhysicalDistribute |
| --------------PhysicalOlapScan[t3] |
| |
| Used: leading(t1 { t2 t3 }) |
| Used: leading(t1 ( t2 t3 )) |
| UnUsed: |
| SyntaxError: |
+-----------------------------------------------+
Expand All @@ -286,7 +286,7 @@ When Leading Hint is not effective, the normal process will be used to generate
3. Bushy Tree

```sql
mysql> explain shape plan select /*+ leading({t1 t2} {t3 t4}) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
mysql> explain shape plan select /*+ leading((t1 t2) (t3 t4)) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
+-----------------------------------------------+
| Explain String |
+-----------------------------------------------+
Expand All @@ -313,7 +313,7 @@ When Leading Hint is not effective, the normal process will be used to generate
4. zig-zag tree

```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3} t4) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
mysql> explain shape plan select /*+ leading(t1 (t2 t3) t4) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
+--------------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+--------------------------------------------------------------------------------------+
Expand Down Expand Up @@ -347,7 +347,7 @@ When Leading Hint is not effective, the normal process will be used to generate
```sql
-------- test outer join which can not swap
-- t1 leftjoin (t2 join t3 on (P23)) on (P12) != (t1 leftjoin t2 on (P12)) join t3 on (P23)
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
+--------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+--------------------------------------------------------------------------------+
Expand All @@ -364,7 +364,7 @@ When Leading Hint is not effective, the normal process will be used to generate
| |
| Hint log: |
| Used: |
| UnUsed: leading(t1 { t2 t3 }) |
| UnUsed: leading(t1 ( t2 t3 )) |
| SyntaxError: |
+--------------------------------------------------------------------------------+
```
Expand All @@ -383,13 +383,13 @@ When Leading Hint is not effective, the normal process will be used to generate

-- (t1 leftjoin t2 on (P12)) leftjoin t3 on (P23) = t1 leftjoin (t2 leftjoin t3 on (P23)) on (P12)
select /*+ leading(t2 t3 t1) SWAP_INPUT(t1) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;

-------- test outer join which can not swap
-- t1 leftjoin (t2 join t3 on (P23)) on (P12) != (t1 leftjoin t2 on (P12)) join t3 on (P23)
-- eliminated to inner join
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
explain graph select /*+ leading(t1 t2 t3) */ * from t1 left join (select * from t2 join t3 on c2 = c3) on c1 = c2;

-- test semi join
Expand Down
12 changes: 6 additions & 6 deletions docs/query-acceleration/tuning/tuning-plan/reordering-join-with-leading-hint.md
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Expand Up @@ -105,7 +105,7 @@ Similarly, the Hint log shows the successfully applied hint: `Used: leading(t1 t
## Case 3: Forcing the Generation of a Right-Deep Tree

```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on t1.c1 = t2.c2 join t3 on t2.c2 = t3.c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 join t2 on t1.c1 = t2.c2 join t3 on t2.c2 = t3.c3;
+----------------------------------------------------------------------------------+
| _Explain_ String(Nereids Planner) |
+----------------------------------------------------------------------------------+
Expand All @@ -121,18 +121,18 @@ mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on
| --------------PhysicalOlapScan[t3] |
| |
| Hint log: |
| Used: leading(t1 { t2 t3 }) |
| Used: leading(t1 ( t2 t3 )) |
| UnUsed: |
| SyntaxError: |
+----------------------------------------------------------------------------------+
```

Similarly, the Hint log shows the successfully applied hint: `Used: leading(t1 { t2 t3 })`.
Similarly, the Hint log shows the successfully applied hint: `Used: leading(t1 ( t2 t3 ))`.

## Case 4: Forcing the Generation of a Bushy Tree

```sql
mysql> explain shape plan select /*+ leading({t1 t2} {t3 t4}) */ * from t1 join t2 on t1.c1 = t2.c2 join t3 on t2.c2 = t3.c3 join t4 on t3.c3 = t4.c4;
mysql> explain shape plan select /*+ leading((t1 t2) (t3 t4)) */ * from t1 join t2 on t1.c1 = t2.c2 join t3 on t2.c2 = t3.c3 join t4 on t3.c3 = t4.c4;
+-----------------------------------------------+
| _Explain_ String |
+-----------------------------------------------+
Expand Down Expand Up @@ -202,7 +202,7 @@ explain shape plan
from
(
select
/*+ leading(orders shuffle {lineitem shuffle part} shuffle {supplier broadcast nation} shuffle partsupp) */
/*+ leading(orders [shuffle] (lineitem [shuffle] part) [shuffle] (supplier [broadcast] nation) [shuffle] partsupp) */
n_name as nation,
extract(year from o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
Expand Down Expand Up @@ -230,7 +230,7 @@ explain shape plan
o_year desc;
```

The above hint specification `/*+ leading(orders shuffle {lineitem shuffle part} shuffle {supplier broadcast nation} shuffle partsupp) */` mixes the two formats of leading and distribute hint. Leading is used to control the relative join order among the overall tables, while shuffle and broadcast are used to specify the shuffle method for specific joins. By combining the two, the connection order and connection method can be flexibly controlled, making it convenient to manually control the expected plan behavior of the user.
The above hint specification `/*+ leading(orders [shuffle] (lineitem [shuffle] part) [shuffle] (supplier [broadcast] nation) [shuffle] partsupp) */` mixes the two formats of leading and distribute hint. Leading is used to control the relative join order among the overall tables, while shuffle and broadcast are used to specify the shuffle method for specific joins. By combining the two, the connection order and connection method can be flexibly controlled, making it convenient to manually control the expected plan behavior of the user.

:::caution Usage Suggestions
- It is recommended to use EXPLAIN to carefully analyze the execution plan to ensure that the Leading Hint can achieve the expected effect.
Expand Down
2 changes: 1 addition & 1 deletion ...usaurus-plugin-content-docs/current/query-acceleration/hints/distribute-hint.md
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Original file line number Diff line number Diff line change
Expand Up @@ -106,7 +106,7 @@ explain shape plan
from
(
select
/*+ leading(orders shuffle {lineitem shuffle part} shuffle {supplier broadcast nation} shuffle partsupp) */
/*+ leading(orders [shuffle] (lineitem [shuffle] part) [shuffle] (supplier [broadcast] nation) [shuffle] partsupp) */
n_name as nation,
extract(year from o_orderdate) as o_year,
l_extendedprice * (1 - l_discount) - ps_supplycost * l_quantity as amount
Expand Down
22 changes: 11 additions & 11 deletions ...docusaurus-plugin-content-docs/current/query-acceleration/hints/leading-hint.md
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Original file line number Diff line number Diff line change
Expand Up @@ -100,7 +100,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =

2. 同时允许使用大括号指定 Join 树形状：
```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on c1 = c2 join t3 on c2=c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 join t2 on c1 = c2 join t3 on c2=c3;
+----------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+----------------------------------------------------------------------------------+
Expand All @@ -116,7 +116,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
| --------------PhysicalOlapScan[t3] |
| |
| Hint log: |
| Used: leading(t1 { t2 t3 }) |
| Used: leading(t1 ( t2 t3 )) |
| UnUsed: |
| SyntaxError: |
+----------------------------------------------------------------------------------+
Expand Down Expand Up @@ -262,7 +262,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
当需要将计划的形状做成右深树、Bushy 树或者 zig-zag 树时，只需加上大括号来限制 plan 的形状即可，无需像 Oracle 使用 swap 从左深树一步步调整。

```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3;
+-----------------------------------------------+
| Explain String |
+-----------------------------------------------+
Expand All @@ -277,7 +277,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
| ------------PhysicalDistribute |
| --------------PhysicalOlapScan[t3] |
| |
| Used: leading(t1 { t2 t3 }) |
| Used: leading(t1 ( t2 t3 )) |
| UnUsed: |
| SyntaxError: |
+-----------------------------------------------+
Expand All @@ -286,7 +286,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
3. Bushy 树

```sql
mysql> explain shape plan select /*+ leading({t1 t2} {t3 t4}) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
mysql> explain shape plan select /*+ leading((t1 t2) (t3 t4)) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
+-----------------------------------------------+
| Explain String |
+-----------------------------------------------+
Expand All @@ -313,7 +313,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
4. zig-zag 树

```sql
mysql> explain shape plan select /*+ leading(t1 {t2 t3} t4) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
mysql> explain shape plan select /*+ leading(t1 (t2 t3) t4) */ * from t1 join t2 on t1.c1 = c2 join t3 on c2 = c3 join t4 on c3 = c4;
+--------------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+--------------------------------------------------------------------------------------+
Expand Down Expand Up @@ -348,7 +348,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
```sql
-------- test outer join which can not swap
-- t1 leftjoin (t2 join t3 on (P23)) on (P12) != (t1 leftjoin t2 on (P12)) join t3 on (P23)
mysql> explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
mysql> explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
+--------------------------------------------------------------------------------+
| Explain String(Nereids Planner) |
+--------------------------------------------------------------------------------+
Expand All @@ -365,7 +365,7 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =
| |
| Hint log: |
| Used: |
| UnUsed: leading(t1 { t2 t3 }) |
| UnUsed: leading(t1 ( t2 t3 )) |
| SyntaxError: |
+--------------------------------------------------------------------------------+
```
Expand All @@ -384,13 +384,13 @@ mysql> explain shape plan select /*+ leading(t2 t1) */ * from t1 join t2 on c1 =

-- (t1 leftjoin t2 on (P12)) leftjoin t3 on (P23) = t1 leftjoin (t2 leftjoin t3 on (P23)) on (P12)
select /*+ leading(t2 t3 t1) SWAP_INPUT(t1) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 left join t3 on c2 = c3;

-------- test outer join which can not swap
-- t1 leftjoin (t2 join t3 on (P23)) on (P12) != (t1 leftjoin t2 on (P12)) join t3 on (P23)
-- eliminated to inner join
explain shape plan select /*+ leading(t1 {t2 t3}) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
explain shape plan select /*+ leading(t1 (t2 t3)) */ * from t1 left join t2 on c1 = c2 join t3 on c2 = c3;
explain graph select /*+ leading(t1 t2 t3) */ * from t1 left join (select * from t2 join t3 on c2 = c3) on c1 = c2;

-- test semi join
Expand Down
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