Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

get subgraph format #1058

Merged
merged 2 commits into from
Oct 15, 2021
Merged

get subgraph format #1058

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
4b756fa
get subgraph format
cooper-lzy Oct 14, 2021
40ec82f
update
cooper-lzy Oct 14, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
51 changes: 26 additions & 25 deletions docs-2.0/3.ngql-guide/16.subgraph-and-path/1.get-subgraph.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,9 +6,8 @@

```ngql
GET SUBGRAPH [WITH PROP] [<step_count> STEPS] FROM {<vid>, <vid>...}
[IN <edge_type>, <edge_type>...]
[OUT <edge_type>, <edge_type>...]
[BOTH <edge_type>, <edge_type>...];
[{IN | OUT | BOTH} <edge_type>, <edge_type>...]
[YIELD [VERTICES AS <vertex_alias>] [,EDGES AS <edge_alias>]];
```

- `WITH PROP`：展示属性。不添加本参数则隐藏属性。
Expand All @@ -19,6 +18,8 @@ GET SUBGRAPH [WITH PROP] [<step_count> STEPS] FROM {<vid>, <vid>...}

- `edge_type`：指定Edge type。可以用`IN`、`OUT`和`BOTH`来指定起始点上该Edge type的方向。默认为`BOTH`。

- `YIELD`：定义需要返回的输出。可以仅返回点或边。必须设置别名。不使用`YIELD`定义输出结果时，默认返回`_vertices`和`_edges`。

!!! note

`GET SUBGRAPH`语句检索的路径类型为`trail`，即检索的路径只有点可以重复，边不可以重复。详情请参见[路径](../../1.introduction/2.1.path.md)。
Expand All @@ -32,13 +33,13 @@ GET SUBGRAPH [WITH PROP] [<step_count> STEPS] FROM {<vid>, <vid>...}
- 查询从点`player100`开始、0~1跳、所有Edge type的子图。

```ngql
nebula> GET SUBGRAPH 1 STEPS FROM "player100";
nebula> GET SUBGRAPH 1 STEPS FROM "player100" YIELD VERTICES AS nodes, EDGES AS relationships;
+-------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+
| _vertices | _edges |
| nodes | relationships |
+-------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+
| [("player100" :player{})] | [[:serve "player100"->"team200" @0 {}], [:follow "player100"->"player101" @0 {}], [:follow "player100"->"player102" @0 {}]] |
| [("player100" :player{})] | [[:follow "player100"->"player101" @0 {}], [:follow "player100"->"player102" @0 {}], [:serve "player100"->"team200" @0 {}]] |
+-------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+
| [("team200" :team{}), ("player101" :player{}), ("player102" :player{})] | [[:follow "player102"->"player101" @0 {}]] |
| [("player101" :player{}), ("player102" :player{}), ("team200" :team{})] | [[:follow "player102"->"player101" @0 {}]] |
+-------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+
```

Expand All @@ -49,24 +50,24 @@ GET SUBGRAPH [WITH PROP] [<step_count> STEPS] FROM {<vid>, <vid>...}
- 查询从点`player100`开始、0~1跳、`follow`类型的入边的子图。

```ngql
nebula> GET SUBGRAPH 1 STEPS FROM "player100" IN follow;
+---------------------------+--------+
| _vertices | _edges |
+---------------------------+--------+
| [("player100" :player{})] | [] |
+---------------------------+--------+
| [] | [] |
+---------------------------+--------+
nebula> GET SUBGRAPH 1 STEPS FROM "player100" IN follow YIELD VERTICES AS nodes, EDGES AS relationships;
+---------------------------+---------------+
| nodes | relationships |
+---------------------------+---------------+
| [("player100" :player{})] | [] |
+---------------------------+---------------+
| [] | [] |
+---------------------------+---------------+
```

因为`player100`没有`follow`类型的入边。所以仅返回点`player100`。

- 查询从点`player100`开始、0~1跳、`serve`类型的出边的子图，同时展示边的属性。

```ngql
nebula> GET SUBGRAPH WITH PROP 1 STEPS FROM "player100" OUT serve;
nebula> GET SUBGRAPH WITH PROP 1 STEPS FROM "player100" OUT serve YIELD VERTICES AS nodes, EDGES AS relationships;
+------------------------------------------------------+-------------------------------------------------------------------------+
| _vertices | _edges |
| nodes | relationships |
+------------------------------------------------------+-------------------------------------------------------------------------+
| [("player100" :player{age: 42, name: "Tim Duncan"})] | [[:serve "player100"->"team200" @0 {end_year: 2016, start_year: 1997}]] |
+------------------------------------------------------+-------------------------------------------------------------------------+
Expand Down Expand Up @@ -102,12 +103,12 @@ nebula> go 1 steps from "A" over follow;
查询到没有多余子图数据时会停止查询，且不会返回空值。

```ngql
nebula> GET SUBGRAPH 100 STEPS FROM "player141" OUT follow;
+-------------------------------------------------------+--------------------------------------------+
| _vertices | _edges |
+-------------------------------------------------------+--------------------------------------------+
| [("player141" :player{age: 43, name: "Ray Allen"})] | [[:follow "player141"->"player124" @0 {}]] |
+-------------------------------------------------------+--------------------------------------------+
| [("player124" :player{age: 33, name: "Rajon Rondo"})] | [[:follow "player124"->"player141" @0 {}]] |
+-------------------------------------------------------+--------------------------------------------+
nebula> GET SUBGRAPH 100 STEPS FROM "player141" OUT follow YIELD VERTICES AS nodes, EDGES AS relationships;
+---------------------------+--------------------------------------------+
| nodes | relationships |
+---------------------------+--------------------------------------------+
| [("player141" :player{})] | [[:follow "player141"->"player124" @0 {}]] |
+---------------------------+--------------------------------------------+
| [("player124" :player{})] | [[:follow "player124"->"player141" @0 {}]] |
+---------------------------+--------------------------------------------+
```