*******************************************************
                Neptune Gremlin Explain
*******************************************************

Query String
============
g.V().union(
    __.hasLabel('VertexType1').limit(1),
    __.hasLabel('VertexType2').limit(1),
    __.hasLabel('VertexType3').limit(1),
    __.hasLabel('VertexType4').limit(1),
    __.hasLabel('VertexType5').limit(1),
    __.hasLabel('VertexType6').limit(1),
    __.hasLabel('VertexType7').limit(1),
    __.hasLabel('VertexType8').limit(1)
)
.fold()
.project('VertexType1', 'VertexType2', 'VertexType3', 'VertexType4', 'VertexType5', 'VertexType6', 'VertexType7', 'VertexType8')
.by(unfold().hasLabel('VertexType1'))
.by(unfold().hasLabel('VertexType2'))
.by(unfold().hasLabel('VertexType3'))
.by(unfold().hasLabel('VertexType4'))
.by(unfold().hasLabel('VertexType5'))
.by(unfold().hasLabel('VertexType6'))
.by(unfold().hasLabel('VertexType7'))
.by(unfold().hasLabel('VertexType8'))


Original Traversal
==================
[GraphStep(vertex,[]), UnionStep([[HasStep([~label.eq(VertexType1)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType2)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType3)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType4)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType5)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType6)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType7)]), RangeGlobalStep(0,1), EndStep], [HasStep([~label.eq(VertexType8)]), RangeGlobalStep(0,1), EndStep]]), FoldStep, ProjectStep([VertexType1, VertexType2, VertexType3, VertexType4, VertexType5, VertexType6, VertexType7, VertexType8],[[UnfoldStep, HasStep([~label.eq(VertexType1)])], [UnfoldStep, HasStep([~label.eq(VertexType2)])], [UnfoldStep, HasStep([~label.eq(VertexType3)])], [UnfoldStep, HasStep([~label.eq(VertexType4)])], [UnfoldStep, HasStep([~label.eq(VertexType5)])], [UnfoldStep, HasStep([~label.eq(VertexType6)])], [UnfoldStep, HasStep([~label.eq(VertexType7)])], [UnfoldStep, HasStep([~label.eq(VertexType8)])]])]

Converted Traversal
===================
Neptune steps:
[
    NeptuneGraphQueryStep(Vertex) {
        JoinGroupNode {
            PatternNode[VL(?1, <~label>, ?2, <~>) . project distinct ?1 .]
            UnionNode {
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?3, <~>) . ContainsFilter(?3 in (<VertexType1>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?4}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?5, <~>) . ContainsFilter(?5 in (<VertexType2>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?6}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?7, <~>) . ContainsFilter(?7 in (<VertexType3>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?8}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?9, <~>) . ContainsFilter(?9 in (<VertexType4>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?10}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?11, <~>) . ContainsFilter(?11 in (<VertexType5>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?12}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?13, <~>) . ContainsFilter(?13 in (<VertexType6>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?14}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?15, <~>) . ContainsFilter(?15 in (<VertexType7>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?16}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?17, <~>) . ContainsFilter(?17 in (<VertexType8>)) .]
                    }, finishers=[limit(1)]
                    Bind {?1 as ?18}
                }
            }
            Bind {Coalesce(?4, ?6, ?8, ?10, ?12, ?14, ?16, ?18) as ?19}
        }, {path=[Vertex(?1):GraphStep, -V-e-r-t-e-x-(-?-4-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-6-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-8-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-0-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-2-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-4-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-6-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-8-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-9-)-:-U-n-i-o-n-S-t-e-p-], maxVarId=20}
    },
    NeptuneTraverserConverterStep
]
+ not converted into Neptune steps: FoldStep,ProjectStep([VertexType1, VertexType2, VertexType3, VertexType4, VertexType5, VertexType6, VertexType7, VertexType8],[[UnfoldStep, HasStep([~label.eq(VertexType1)])], [UnfoldStep, HasStep([~label.eq(VertexType2)])], [UnfoldStep, HasStep([~label.eq(VertexType3)])], [UnfoldStep, HasStep([~label.eq(VertexType4)])], [UnfoldStep, HasStep([~label.eq(VertexType5)])], [UnfoldStep, HasStep([~label.eq(VertexType6)])], [UnfoldStep, HasStep([~label.eq(VertexType7)])], [UnfoldStep, HasStep([~label.eq(VertexType8)])]]),

Optimized Traversal
===================
Neptune steps:
[
    NeptuneGraphQueryStep(Vertex) {
        JoinGroupNode {
            UnionNode {
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?3=<VertexType1>, <~>) .], {estimatedCardinality=251669484}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?4}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?5=<VertexType2>, <~>) .], {estimatedCardinality=99941106}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?6}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?7=<VertexType3>, <~>) .], {estimatedCardinality=221647266}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?8}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?9=<VertexType4>, <~>) .], {estimatedCardinality=78325288}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?10}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?11=<VertexType5>, <~>) .], {estimatedCardinality=39299200}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?12}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?13=<VertexType6>, <~>) .], {estimatedCardinality=210783068}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?14}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?15=<VertexType7>, <~>) .], {estimatedCardinality=98800974}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?16}
                }
                JoinGroupNode {
                    JoinGroupNode {
                        PatternNode[VL(?1, <~label>, ?17=<VertexType8>, <~>) .], {estimatedCardinality=99342578}
                    }, finishers=[limit(1)], {estimatedCardinality=1}
                    Bind {?1 as ?18}
                }
            }
            Bind {Coalesce(?4, ?6, ?8, ?10, ?12, ?14, ?16, ?18) as ?19}
        }, {path=[Vertex(?1):GraphStep, -V-e-r-t-e-x-(-?-4-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-6-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-8-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-0-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-2-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-4-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-6-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-8-)-:-G-r-a-p-h-S-t-e-p-, -V-e-r-t-e-x-(-?-1-9-)-:-U-n-i-o-n-S-t-e-p-], maxVarId=20}
    },
    NeptuneTraverserConverterStep,
    NeptuneMemoryTrackerStep
]
+ not converted into Neptune steps: FoldStep,ProjectStep([VertexType1, VertexType2, VertexType3, VertexType4, VertexType5, VertexType6, VertexType7, VertexType8],[[UnfoldStep, NeptuneHasStep([~label.eq(VertexType1)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType2)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType3)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType4)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType5)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType6)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType7)])], [UnfoldStep, NeptuneHasStep([~label.eq(VertexType8)])]]),

WARNING: >> [FoldStep] << (or one of the children for each step) is not supported natively yet

Predicates
==========
# of predicates: 31