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Steps O-T

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option

  • 功能:(修饰符)指定分支查询的条件。

  • 备注:需要与branch()结合使用。

optional

  • 功能:(branch)如果子遍历能产生结果,则返回遍历结果;否则,返回输入object。

// 输出朋友关系或者没朋友的可怜人自己的信息
g("thinkerpop").V("1;2;4;6").hasLabel("person").optional(outE("knows"))
==> {"label":"knows","pk":"1","sk":"4","weight":1.0}
==> {"label":"knows","pk":"1","sk":"2","weight":0.5}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

or

  • 功能:(filter)返回“至少在一个子遍历能产生结果”的输入

// 年龄为27或者至少有两个朋友的人
g("thinkerpop").V("1;2;4;6").hasLabel("person").or(outE("knows").count().is(P.gte(2)),filter("age=27"))
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}

order

  • 功能:(map)排序

  • 备注:

    • 单步可以被by()修饰,用于指定排序规则以及升序incr/降序decr/乱序shuffle

      • 默认按照自身值进行排序,排序规则支持指定字段值和子遍历。

      • 默认为升序

      • 支持通过多个by()指定多个排序规则

    • 单步会隐式插入barrier()

// 按照pk升序,pk相同则按照sk降序
g("thinkerpop").E("1;2;3;4;5;6").hasLabel("created").order().by("pk").by("sk",Order.decr)
==> {"label":"created","pk":"1","sk":"3","weight":0.4}
==> {"label":"created","pk":"4","sk":"5","weight":1.0}
==> {"label":"created","pk":"4","sk":"3","weight":0.4}
==> {"label":"created","pk":"6","sk":"3","weight":0.2}

// 按照人脉数量降序
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").order().by(outE("knows").count(),Order.decr)
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

// 年龄的乱序
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").values("age").order().by(Order.shuffle)
==> 32
==> 35
==> 29
==> 27

out

  • 功能:(实体)从一个顶点跳转到关联的顶点。

  • 备注:

    • 单步仅支持图访问方式。

      • 通过参数指定要跳转的边在图中对应的label

      • 不指定参数时,默认会访问所有关联的边。

    • 单步会被拆解为outE().limit(50).inV(),即出边增加了50的截断。如果不满足需求,请使用outE().limit(300).inV()模式。

      出于系统保护的角度,出边不能超过50000

    • out().out()会被优化拆解为outE().limit(50).outE().limit(50).inV()

      • 用于节约一次顶点的访问。

      • 第一次ouE()关联边skey值,即为第二次outE()关联边的pkey值。

      • 如果后续遍历中存在path(),则此优化不生效。

g("thinkerpop").V("1").hasLabel("person").out("knows")
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}

g("thinkerpop").V("1").hasLabel("person").out()
==> {"label":"software","lang":"java","name":"lop","pk":"3"}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}

outE

  • 功能:(实体)从一个顶点跳转到关联的边

  • 备注:

    • 图访问方式:通过参数指定要跳转的边在图中对应的label

      • 不指定参数时,默认会访问所有关联的边。

// 默认输入顶点的pkey为跳转字段
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").outE("knows")
==> {"label":"knows","pk":"1","sk":"4","weight":1.0}
==> {"label":"knows","pk":"1","sk":"2","weight":0.5}

g("thinkerpop").V("1").hasLabel("person").outE("knows","created")
==> {"label":"created","pk":"1","sk":"3","weight":0.4}
==> {"label":"knows","pk":"1","sk":"4","weight":1.0}
==> {"label":"knows","pk":"1","sk":"2","weight":0.5}

P

  • 功能:(函数)描述比较逻辑。

  • 格式

类型

名称

含义

例子

基础

P.eq

相等

P.eq(25)

P.neq

不相等

P.neq(25)

P.gt

大于

P.gt(25)

P.gte

大于等于

P.gte(25)

P.lt

小于

P.lt(25)

P.lte

小于等于

P.lte(25)

P.inside

在范围内:(a, b)

P.inside(25, 32)

P.outside

不在范围内:(-inf, a) U (b, inf)

P.outside(25, 32)

P.between

在之间:[a, b)

P.between(25, 32)

P.within

在集合内

P.within(25, 32, 33, 35)

P.without

不在集合内

P.without(25, 32, 33, 35)

合成

and

P.gt(25) and P.lt(30)

or

P.eq(25) or P.eq(30)

negate

P.eq(25).negate()

  • 备注

    • 仅支持数字类型和string

    • 适用于is()has()等filter类型的单步

    • P表达式的区别

      • P:适用于一个参数的场景,参数可以没有名字

      • 表达式:适用于多个参数的场景,参数必须有名字

      • 二者的功能存在部分重叠,用户可以量体裁衣

// 年龄为27或者至少有两个朋友的人
g("thinkerpop").V("1;2;4;6").hasLabel("person").or(outE("knows").count().is(P.gte(2)),values("age").is(P.eq(27)))
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
// 等同于
// or()的第一个子遍历没有名字,只能使用P;第二个参数为age,可以通过filter使用表达式代替
g("thinkerpop").V("1;2;4;6").hasLabel("person").or(outE("knows").count().is(P.gte(2)),filter("age=27"))

path

  • 功能(map):返回遍历的路径

  • 备注

    • path()仅展示每个单步的结果。如果out()需要展示边的信息,则需要显示地使用outE().inV()

    • 单步可以被by()修饰,用于指定路径上需要记录的字段

    • 单步可以定制PathRecordStrategy策略,用于指定路径需要记录的信息类型

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").out().out().values("name").path()
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"lop","pk":"3"},"lop"],"labels":[[],[],[],[]]}
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"ripple","pk":"5"},"ripple"],"labels":[[],[],[],[]]}

// 显式调用outE().inV(),展示边的信息
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").outE().inV().outE().inV().values("name").path()
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"knows","pk":"1","sk":"4","weight":1.0},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"created","pk":"4","sk":"3","weight":0.4},{"label":"software","lang":"java","name":"lop","pk":"3"},"lop"],"labels":[[],[],[],[],[],[]]}
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"knows","pk":"1","sk":"4","weight":1.0},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"created","pk":"4","sk":"5","weight":1.0},{"label":"software","lang":"java","name":"ripple","pk":"5"},"ripple"],"labels":[[],[],[],[],[],[]]}

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").out().out().path().by("name")
==> {"value":["marko","josh","lop"],"labels":[[],[],[]]}
==> {"value":["marko","josh","ripple"],"labels":[[],[],[]]}

PathRecordStrategy

  • 功能:(策略)定制path()记录的信息类型

  • 格式:信息类型分为下列三种

  • 此策略为IGraph自研扩展的策略

    • PathRecord.vertex:顶点

    • PathRecord.edge:边

    • PathRecord.map:map类型

  • 备注:

    • 默认记录所有信息类型

    • 策略需要与withStrategies()联合使用

    • 策略有利于减少数据的传输量

// 默认记录所有信息类型
g("thinkerpop").V("4").hasLabel("person").outE().inV().path()
==> {"value":[{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"created","pk":"4","sk":"3","weight":0.4},{"label":"software","lang":"java","name":"lop","pk":"3"}],"labels":[[],[],[]]}
==> {"value":[{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"created","pk":"4","sk":"5","weight":1.0},{"label":"software","lang":"java","name":"ripple","pk":"5"}],"labels":[[],[],[]]}

// 只记录顶点信息
g("thinkerpop").V("4").withStrategies(PathRecordStrategy(PathRecord.vertex)).hasLabel("person").outE().inV().path()
==> {"value":[{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"lop","pk":"3"}],"labels":[[],[]]},
==> {"value":[{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"ripple","pk":"5"}],"labels":[[],[]]}

// 只记录边信息
g("thinkerpop").V("4").withStrategies(PathRecordStrategy(PathRecord.edge)).hasLabel("person").outE().inV().path()
==> {"value":[{"label":"created","pk":"4","sk":"3","weight":0.4}],"labels":[[]]}
==> {"value":[{"label":"created","pk":"4","sk":"5","weight":1.0}],"labels":[[]]}

project

  • 功能:(map)单步可以将输入objects映射成map<string,object>

  • 备注:单步可以被by()修饰,用于指定映射的value值

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").project("a","b").by(outE("knows").count()).by("age").order().by(select("b"))
==> {"\"a\"":0,"\"b\"":27}
==> {"\"a\"":2,"\"b\"":29}
==> {"\"a\"":0,"\"b\"":32}
==> {"\"a\"":0,"\"b\"":35}

// 每个人创造的物品数量和认识的朋友数量
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").project("created","knows").by(outE("created").count()).by(outE("knows").count())
==> {"\"created\"":1,"\"knows\"":2}
==> {"\"created\"":2,"\"knows\"":0}
==> {"\"created\"":0,"\"knows\"":0}
==> {"\"created\"":1,"\"knows\"":0}

properties

  • 功能:(map)返回字段名和字段值

  • 备注:

    • 支持指定返回,默认返回所有

    • values()支持返回字段值

g("thinkerpop").V("1;2").hasLabel("person").properties()
==> {"age":29}
==> {"name":"marko"}
==> {"pk":"1"}
==> {"age":27}
==> {"name":"vadas"}
==> {"pk":"2"}

g("thinkerpop").V("1;2").hasLabel("person").properties("name","age")
==> {"age":29}
==> {"name":"marko"}
==> {"age":27}
==> {"name":"vadas"}

propertyMap

  • 功能:(map)返回字段名和字段值的map

  • 备注:支持指定返回,默认返回所有

g("thinkerpop").V("1;2").hasLabel("person").propertyMap()
==> {"\"age\"":{"age":29},"\"name\"":{"name":"marko"},"\"pk\"":{"pk":"1"}}
==> {"\"age\"":{"age":27},"\"name\"":{"name":"vadas"},"\"pk\"":{"pk":"2"}}

g("thinkerpop").V("1;2").hasLabel("person").propertyMap("name","age")
==> {"\"age\"":{"age":29},"\"name\"":{"name":"marko"}}
==> {"\"age\"":{"age":27},"\"name\"":{"name":"vadas"}}

PushDownStrategy

  • 功能:(策略)指定获取sideEffect的单步下推至存储层执行

  • 备注:在偏计算的场景,将获取sideEffect的单步下推至存储层执行,有利于减少数据的传输

  • 此策略为IGraph自研扩展的策略

// 每个人和其他人年龄乘积的最大值
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").aggregate("x").by("age").V("1;2;3;4;5;6").hasLabel("person").values("age").as("y").local(select("x").unfold().math("_ * y").max())
==> 1015
==> 1120
==> 945
==> 1225

// 将计算最大值的逻辑下推到“获取y之后立刻执行计算”,减少y需要保存的时长
g("thinkerpop").withStrategies(PushDownStrategy("x")).V("1;2;3;4;5;6").hasLabel("person").aggregate("x").by("age").V("1;2;3;4;5;6").hasLabel("person").values("age").as("y").local(select("x").unfold().math("_ * y").max())
==> 1015
==> 1120
==> 945
==> 1225

range

  • 功能:(filter)截断。

  • 格式:range(low,high)low为uint32类型,high为int64类型,建议high<50000

  • 备注:如果high为-1的话,则返回low往后的所有结果;否则,high>low必须成立。

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").order().by("pk").range(1,2)
==> {"label":"person","age":27,"name":"vadas","pk":"2"}

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").order().by("pk").range(1,-1)
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").order().by("pk").range(1,0)
==> {"ErrorCode":20040,"ErrorDescription":"gremlin 'range(global)' step invalid (low(1) > high(0) in 'range')"}

repeat

  • 功能:(branch)循环遍历

  • 备注:

    • 单步可以和times()util()等联合使用,以指定循环停止的条件。

    • 单步可以和emit()联合使用,用于记录循环的中间结果。

    • 出于系统保护的考虑,请不要执行bad query。例如:在有环图中无限制的repeat。

    • 出于系统保护的考虑,请在循环内的每一次跳转指定limit()截断,每一度都不能超过5w个结果。

# 经过两次out,得到遍历路径。
g("thinkerpop").V("1").hasLabel("person").repeat(out()).times(2).path().by("name")
==> {"value":["marko","josh","lop"],"labels":[[],[],[]]}
==> {"value":["marko","josh","ripple"],"labels":[[],[],[]]}

# 禁止在 有环图 中执行until
# 从指定节点出发,进行广度优先搜索,直到遇到ripple节点为止。
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").until(has("name","ripple")).repeat(out()).path().by("name")
==> {"value":["marko","josh","ripple"],"labels":[[],[],[]]}
==> {"value":["josh","ripple"],"labels":[[],[]]}

# emit() - 遍历两度,并且中间遇到的路径输出出来。
g("thinkerpop").V("1").hasLabel("person").repeat(out()).times(2).emit().path().by("name")
==> {"value":["marko","lop"],"labels":[[],[]]}
==> {"value":["marko","josh"],"labels":[[],[]]}
==> {"value":["marko","vadas"],"labels":[[],[]]}
==> {"value":["marko","josh","lop"],"labels":[[],[],[]]}
==> {"value":["marko","josh","ripple"],"labels":[[],[],[]]}

# emit() - 遍历两度,并且中间遇到的路径输出出来:包含还没有开始进行repeat的时候的路径。
g("thinkerpop").V("1").hasLabel("person").emit().repeat(out()).times(2).path().by("name")
==>[marko]
==> {"value":["marko"],"labels":[[]]}
==> {"value":["marko","lop"],"labels":[[],[]]}
==> {"value":["marko","josh"],"labels":[[],[]]}
==> {"value":["marko","josh","lop"],"labels":[[],[],[]]}
==> {"value":["marko","josh","ripple"],"labels":[[],[],[]]}
==> {"value":["marko","vadas"],"labels":[[],[]]}

sack

  • 功能:(map)返回实体的sack值

  • 备注:sack值的初始化值、分裂规则和合并规则详见withSack()

sample

  • 功能:(filter)采样

  • 格式:sample([Sample.upsampling,][Sample.duplicatable,]NUM)[by(field)]NUM为uint32类型

    • Sample.duplicatable指定不去重,允许输出object的bulk超过其输入bulk。即输入a a b c,采样3,去重最多得到2个a,不去重可能得到3个a。

    • Sample.upsampling指定上采样,当输入的object的bulk总和小于采样数时,上采样可以保证一定会返回指定个数的结果(除非0结果)。如果上采样实际生效了,那么指定不去重会失效。

    • 默认去重且不上采样。

  • 备注:

    • 默认随机采样。

    • 单步可以被by()修饰,用于指定某个字段的值作为采样权重,权重越高采样到的概率越大。

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").outE("created").sample(Sample.upsampling,Sample.duplicatable,5).by("weight")
==> {"label":"created","pk":"1","sk":"3","weight":0.4}
==> {"label":"created","pk":"4","sk":"5","weight":1.0}
==> {"label":"created","pk":"4","sk":"5","weight":1.0}
==> {"label":"created","pk":"4","sk":"5","weight":1.0}
==> {"label":"created","pk":"6","sk":"3","weight":0.2}

select

  • 功能:(map)返回as()打标的标签值

  • 备注:

    • 单步获取多个标签值时会得到map<label,objects>

    • 单步可被by()修饰,用于指定获取标签的某个字段。

    • 单步可以和Pop.firstPop.lastPop.all联合使用,分别代表选择路径上标签的第一次出现、最后一次出现、和所有出现。

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").as("x").select("x")
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

// filter单步以带标的objects作为输入
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").as("x").filter("age>=32").select("x")
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

// 单步可通过as()被多个标签关联
// select()获取多个标签值时会得到map<label,objects>
// select()被by()修饰,指定获取label的哪个字段
g("thinkerpop").V("1;2").hasLabel("person").as("x","y","z").select("x","y","z").by("pk").by("name").by("age")
==> {"\"x\"":"1","\"y\"":"marko","\"z\"":29}
==> {"\"x\"":"2","\"y\"":"vadas","\"z\"":27}

// 第一次出现的a标签值
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").as("a").repeat(out().as("a")).times(2).select(Pop.first,"a")
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":29,"name":"marko","pk":"1"}

// 最后一次出现的a标签值
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").as("a").repeat(out().as("a")).times(2).select(Pop.last,"a")
==> {"label":"software","lang":"java","name":"lop","pk":"3"}
==> {"label":"software","lang":"java","name":"ripple","pk":"5"}

// 所有出现的a标签值,等价于select("a")
g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").as("a").repeat(out().as("a")).times(2).select(Pop.all,"a")
==> [{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"lop","pk":"3"}]
==> [{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"ripple","pk":"5"}]

simplePath

  • 功能:(filter)返回无环的路径

  • 备注:

    • 单步可以被by()修饰,用于指定有环路径上需要记录的字段

    • cyclePath()返回有环的路径

g("thinkerpop").V("1").hasLabel("person").out().out().simplePath().path()
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"lop","pk":"3"}],"labels":[[],[],[]]}
==> {"value":[{"label":"person","age":29,"name":"marko","pk":"1"},{"label":"person","age":32,"name":"josh","pk":"4"},{"label":"software","lang":"java","name":"ripple","pk":"5"}

g("thinkerpop").V("1").hasLabel("person").out().out().simplePath().path().by("name")
==> {"value":["marko","josh","lop"],"labels":[[],[],[]]}
==>{"value":["marko","josh","ripple"],"labels":[[],[],[]]}

store

  • 功能:(sideEffect)在遍历过程中,将输入objects聚合成一个list<object>,并保存在sideEffect。

  • 备注:

    • 单步不会影响输入objects,下一个单步仍然以objects作为输入。

    • 单步生成的list<object>是只读的,在后续遍历的任意位置可以通过cap()取值。

      • PS:不推荐通过select()取值。由于select()对每个实体都会返回一个list<object>,多个实体就会返回多个一样的list<object>。

    • 单步可以被by()修饰,用于指定聚合的字段值。

    • 使用aggregate()可以阻塞地实现聚合。

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").store("x").by("name")
==> {"label":"person","age":29,"name":"marko","pk":"1"}
==> {"label":"person","age":32,"name":"josh","pk":"4"}
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").store("x").by("name").cap("x")
==> ["josh","marko","peter","vadas"]

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").store("x").by("name").filter("age>=32").cap("x")
==> ["josh","marko","peter","vadas"]

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").store("x").by("name").outE("knows").store("y").cap("x","y").dedup()
==> {"\"x\"":["josh","marko","peter","vadas"],"\"y\"":[{"label":"knows","pk":"1","sk":"2","weight":0.5},{"label":"knows","pk":"1","sk":"4","weight":1.0}]}

sum

  • 功能:(map)计算输入objects的总和。

  • 备注:

    • 单步仅支持数字类型(非bool类型)的输入

    • sum(Scope.local)支持迭代器类型的输入,并且容器内的元素必须是数字类型(非bool类型)

    • 单步会隐式地插入barrier()

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").values("age").sum()
==> 123

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").values("age").fold().sum(Scope.local)
==> 123

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").aggregate("x").by("age").cap("x").sum(Scope.local)
==> 123

T

  • 功能:(函数)提取输入元素的信息

  • 格式

    • T.id:返回实体的pkey字段值

    • T.label:返回实体的label(在图中对应的label)

    • T.key:返回元素的字段名

    • T.value:返回元素的字段值

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").has(T.id,P.eq("1"))
==> {"label":"person","age":29,"name":"marko","pk":"1"}

// 两度跳转之后,没有person了,都是software
g("thinkerpop").V("1").hasLabel("person").out().out().has(T.label,P.eq("person"))
==> 空结果

// 按照字段名进行排序
g("thinkerpop").V("1").hasLabel("person").properties().order().by(T.key)
==> {"age":29}
==> {"name":"marko"}
==> {"pk":"1"}

// 按照字段值进行排序
g("thinkerpop").V("1").hasLabel("person").properties().order().by(T.value)
==> {"age":29}
==> {"pk":"1"}
==> {"name":"marko"}

tail

  • 功能:(filter)截断。保留最后NUM个结果。

  • 格式:tail(NUM)NUM为uint32类型,建议NUM<50000

  • 备注

    • limt()用于保留前NUM个结果

    • 单步会隐式地插入barrier()

g("thinkerpop").V("1;2;3;4;5;6").hasLabel("person").tail(2)
==> {"label":"person","age":27,"name":"vadas","pk":"2"}
==> {"label":"person","age":35,"name":"peter","pk":"6"}

times

  • 功能:(修饰符)指定循环遍历的次数

  • 备注:需要与repeat()联合使用

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