102.adoc

Gremlin Cheat Sheet 102

Paths

Path Filters

Steps	Meaning
simplePath()	keep simple, non-cyclic paths (no element must appear twice or more in the current path)
cyclicPath()	keep cyclic paths (at least one element must appear twice or more in the current path)

Examples

gremlin> g = TinkerFactory.createModern().traversal()
==>graphtraversalsource[tinkergraph[vertices:6 edges:6], standard]
gremlin> g.V(1).out().in().simplePath().path()
==>[v[1],v[3],v[4]]
==>[v[1],v[3],v[6]]
gremlin> g.V(1).out().in().cyclicPath().path()
==>[v[1],v[3],v[1]]
==>[v[1],v[2],v[1]]
==>[v[1],v[4],v[1]]

Variables

Path-local Variables

Steps	Meaning
sack(operator)	assign or compute a path-local variable
sack()	emit the current sack value
as(label)…​select(Pop, label)	select values from previously labeled steps

Examples

gremlin> g = TinkerFactory.createModern().traversal()
==>graphtraversalsource[tinkergraph[vertices:6 edges:6], standard]
gremlin> g.V(1).
......1>   sack(assign).
......2>     by("age").
......3>   out("knows").
......4>   sack(sum).
......5>     by("age").
......6>   sack().
......7>   path().
......8>     by("age").by("age").by()
==>[29,27,56]
==>[29,32,61]
gremlin> g.V(1).as("a").out("knows").as("a").
......1>   select(last, "a")
==>v[2]
==>v[4]
gremlin> g.V(1).as("a").out("knows").as("a").
......1>   select(first, "a")
==>v[1]
==>v[1]
gremlin> g.V(1).as("a").out("knows").as("a").
......1>   select(all, "a")
==>[v[1],v[2]]
==>[v[1],v[4]]

Pattern Matching

Steps	Meaning
match(traversals)	attempts to find matches for the provided patterns in the underlying graph
where(traversal)	puts contraints on labeled steps

Examples

gremlin> g = TinkerFactory.createGratefulDead().traversal()
==>graphtraversalsource[tinkergraph[vertices:808 edges:8049], standard]
gremlin> g.V().match(
......1>     __.as("a").has("name", "Garcia"),
......2>     __.as("a").in("writtenBy").as("b"),
......3>     __.as("a").in("sungBy").as("b")).
......4>   select("b").values("name")
==>CREAM PUFF WAR
==>CRYPTICAL ENVELOPMENT
gremlin> g.V().match(
......1>     __.as("a").in("writtenBy").as("b"),
......2>     __.as("a").in("sungBy").as("b")).
......3>   where(__.as("a").has("name", "Garcia")).
......4>   select("b").values("name")
==>CREAM PUFF WAR
==>CRYPTICAL ENVELOPMENT
gremlin> g.V().has("artist","name","Garcia").as("a").
......1>   in("writtenBy").as("b").
......2>   where(__.as("a").in("sungBy").as("b")).
......3>   values("name")
==>CREAM PUFF WAR
==>CRYPTICAL ENVELOPMENT

Gremlin Cheat Sheet 101 (Basic Steps)