From 3f945600625954dbd470ca753a91ce7533e51762 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9C=B1=E6=99=93=E9=9D=92?=
 <86282370+izhuxiaoqing@users.noreply.github.com>
Date: Fri, 15 Oct 2021 16:01:55 +0800
Subject: [PATCH] update lookup

---
 .../keywords-and-reserved-words.md            |  1 +
 .../7.general-query-statements/5.lookup.md    | 69 +++++++++++++------
 2 files changed, 48 insertions(+), 22 deletions(-)

diff --git a/docs-2.0/3.ngql-guide/1.nGQL-overview/keywords-and-reserved-words.md b/docs-2.0/3.ngql-guide/1.nGQL-overview/keywords-and-reserved-words.md
index 011c85ba50a..616d73dbb0c 100644
--- a/docs-2.0/3.ngql-guide/1.nGQL-overview/keywords-and-reserved-words.md
+++ b/docs-2.0/3.ngql-guide/1.nGQL-overview/keywords-and-reserved-words.md
@@ -43,6 +43,7 @@ RETURN
 DESCRIBE
 DESC
 VERTEX
+VERTICES
 EDGE
 EDGES
 UPDATE
diff --git a/docs-2.0/3.ngql-guide/7.general-query-statements/5.lookup.md b/docs-2.0/3.ngql-guide/7.general-query-statements/5.lookup.md
index 1299379211c..6652042e09a 100644
--- a/docs-2.0/3.ngql-guide/7.general-query-statements/5.lookup.md
+++ b/docs-2.0/3.ngql-guide/7.general-query-statements/5.lookup.md
@@ -1,5 +1,7 @@
 # LOOKUP
 
+<!-- This topic needs to be modified after compulsory use of YIELD in 3.0. Refer to https://confluence.nebula-graph.io/pages/viewpage.action?pageId=10723963 -->
+
 The `LOOKUP` statement traverses data based on indexes. You can use `LOOKUP` for the following purposes:
 
 - Search for the specific data based on conditions defined by the `WHERE` clause.
@@ -35,7 +37,7 @@ Before using the `LOOKUP` statement, make sure that at least one index is create
 ```ngql
 LOOKUP ON {<vertex_tag> | <edge_type>} 
 [WHERE <expression> [AND <expression> ...]] 
-[YIELD <return_list>];
+[YIELD <return_list> [AS <alias>]];
 
 <return_list>
     <prop_name> [AS <col_alias>] [, <prop_name> [AS <prop_alias>] ...];
@@ -43,11 +45,12 @@ LOOKUP ON {<vertex_tag> | <edge_type>}
 
 - `WHERE <expression>`: filters data with specified conditions. Both `AND` and `OR` are supported between different expressions. For more information, see [WHERE](../8.clauses-and-options/where.md).
 
-- `YIELD <return_list>`: specifies the results to be returned and the format of the results.
+- `YIELD`: Define the output to be returned.
+
+  - When you `LOOKUP` a Tag, the defined properties and `VertexID` are returned. If there is no `YIELD` clause, `VertexID` is returned.
+  - When you `LOOKUP` an Edge type, the defined properties, `SrcVertexID`, `DstVertexID`, and `rank` are returned. If there is no `YIELD` clause, `SrcVertexID`, `DstVertexID`, and `rank` are returned.
 
-- If there is a `WHERE` clause but no `YIELD` clause:
-  - The Vertex ID is returned when you `LOOKUP` a tag.
-  - The source vertex ID, destination vertex ID, and rank of the edge are returned when `LOOKUP` an edge type.
+- `AS`: Set an alias.
 
 ## Limitations of using `WHERE` in `LOOKUP`
 
@@ -75,31 +78,53 @@ nebula> REBUILD TAG INDEX index_player;
 
 nebula> LOOKUP ON player \
         WHERE player.name == "Tony Parker";
-============
-| VertexID |
-============
-| 101      |
-------------
++-------------+
+| VertexID    |
++-------------+
+| "player101" |
++-------------+
 
 nebula> LOOKUP ON player \
         WHERE player.name == "Tony Parker" \
+        YIELD player.name AS name, player.age AS age;
++-------------+---------------+-----+
+| VertexID    | name          | age |
++-------------+---------------+-----+
+| "player101" | "Tony Parker" | 36  |
++-------------+---------------+-----+
+
+nebula> LOOKUP ON player \
+        WHERE player.age  > 45;
++-------------+
+| VertexID    |
++-------------+
+| "player144" |
++-------------+
+| "player140" |
++-------------+
+
+nebula> LOOKUP ON player \
+        WHERE player.name STARTS WITH "B" \
+        AND player.age IN [22,30] \
         YIELD player.name, player.age;
-=======================================
-| VertexID | player.name | player.age |
-=======================================
-| 101      | Tony Parker | 36         |
----------------------------------------
++-------------+-----------------+------------+
+| VertexID    | player.name     | player.age |
++-------------+-----------------+------------+
+| "player149" | "Ben Simmons"   | 22         |
++-------------+-----------------+------------+
+| "player134" | "Blake Griffin" | 30         |
++-------------+-----------------+------------+
 
 nebula> LOOKUP ON player \
         WHERE player.name == "Kobe Bryant" \
         YIELD player.name AS name |\
         GO FROM $-.VertexID OVER serve \
         YIELD $-.name, serve.start_year, serve.end_year, $$.team.name;
-==================================================================
-| $-.name     | serve.start_year | serve.end_year | $$.team.name |
-==================================================================
-| Kobe Bryant | 1996             | 2016           | Lakers       |
-------------------------------------------------------------------
++---------------+------------------+----------------+--------------+
+| $-.name       | serve.start_year | serve.end_year | $$.team.name |
++---------------+------------------+----------------+--------------+
+| "Kobe Bryant" | 1996             | 2016           | "Lakers"     |
++---------------+------------------+----------------+--------------+
 ```
 
 ## Retrieve Edges
@@ -186,7 +211,7 @@ For example, if there is a `player` tag with a `name` property and an `age` prop
     
     nebula> LOOKUP ON player;
     +-------------+
-    | _vid        |
+    |  VertexID   |
     +-------------+
     | "player100" |
     +-------------+
@@ -215,7 +240,7 @@ For example, if there is a `player` tag with a `name` property and an `age` prop
 
     nebula)> LOOKUP ON like;
     +-------------+----------+-------------+
-    | _src        | _ranking | _dst        |
+    | VertexID    | DstVID   | _dst        |
     +-------------+----------+-------------+
     | "player100" | 0        | "player101" |
     +-------------+----------+-------------+