From c4cfe3294006430c035b90dcd78482885663e0ef Mon Sep 17 00:00:00 2001 From: knqiufan <34114995+knqiufan@users.noreply.github.com> Date: Sun, 7 Jan 2024 21:18:30 +0800 Subject: [PATCH] add annotation to some examples of `comparison` clause as titled --- docs-2.0-zh/3.ngql-guide/5.operators/1.comparison.md | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/docs-2.0-zh/3.ngql-guide/5.operators/1.comparison.md b/docs-2.0-zh/3.ngql-guide/5.operators/1.comparison.md index 955f0531c34..7cab419986f 100644 --- a/docs-2.0-zh/3.ngql-guide/5.operators/1.comparison.md +++ b/docs-2.0-zh/3.ngql-guide/5.operators/1.comparison.md @@ -119,6 +119,7 @@ nebula> YIELD 1 != '1'; ### `IS [NOT] NULL` ```ngql +# 返回关于 null 的一些判断结果。 nebula> RETURN null IS NULL AS value1, null == null AS value2, null != null AS value3; +--------+----------+----------+ | value1 | value2 | value3 | @@ -126,6 +127,7 @@ nebula> RETURN null IS NULL AS value1, null == null AS value2, null != null AS v | true | __NULL__ | __NULL__ | +--------+----------+----------+ +# 返回关于 NULL 的一些属性信息。 nebula> RETURN length(NULL), size(NULL), count(NULL), NULL IS NULL, NULL IS NOT NULL, sin(NULL), NULL + NULL, [1, NULL] IS NULL; +--------------+------------+-------------+--------------+------------------+-----------+-------------+------------------+ | length(NULL) | size(NULL) | count(NULL) | NULL IS NULL | NULL IS NOT NULL | sin(NULL) | (NULL+NULL) | [1,NULL] IS NULL | @@ -133,6 +135,7 @@ nebula> RETURN length(NULL), size(NULL), count(NULL), NULL IS NULL, NULL IS NOT | __NULL__ | __NULL__ | 0 | true | false | __NULL__ | __NULL__ | false | +--------------+------------+-------------+--------------+------------------+-----------+-------------+------------------+ +# 创建 map 数据,判断 map 的 name 属性是否不为 NULL。 nebula> WITH {name: null} AS `map` \ RETURN `map`.name IS NOT NULL; +----------------------+ @@ -141,6 +144,7 @@ nebula> WITH {name: null} AS `map` \ | false | +----------------------+ +# 创建 map1、map2、map3 的数据,并判断返回其 name 属性是否为 NULL。 nebula> WITH {name: 'Mats', name2: 'Pontus'} AS map1, \ {name: null} AS map2, {notName: 0, notName2: null } AS map3 \ RETURN map1.name IS NULL, map2.name IS NOT NULL, map3.name IS NULL; @@ -150,6 +154,7 @@ nebula> WITH {name: 'Mats', name2: 'Pontus'} AS map1, \ | false | false | true | +-------------------+-----------------------+-------------------+ +# 查询所有 Tag 为 player 的点数据,判断并返回点的 age 属性是否为 NULL、name 属性是否不为 NULL、empty 属性是否为 NULL。 nebula> MATCH (n:player) \ RETURN n.player.age IS NULL, n.player.name IS NOT NULL, n.player.empty IS NULL; +----------------------+---------------------------+------------------------+ @@ -163,6 +168,7 @@ nebula> MATCH (n:player) \ ### `IS [NOT] EMPTY` ```ngql +# 判断 null 是否不存在。 nebula> RETURN null IS EMPTY; +---------------+ | NULL IS EMPTY | @@ -170,6 +176,7 @@ nebula> RETURN null IS EMPTY; | false | +---------------+ +# 判断 a 字符串是否存在。 nebula> RETURN "a" IS NOT EMPTY; +------------------+ | "a" IS NOT EMPTY | @@ -177,6 +184,7 @@ nebula> RETURN "a" IS NOT EMPTY; | true | +------------------+ +# 遍历所有 player100 指向的目的点,并返回目的点数据 name 属性存在的点 id。 nebula> GO FROM "player100" OVER * WHERE properties($$).name IS NOT EMPTY YIELD dst(edge); +-------------+ | dst(EDGE) |