Insert or update vertex using Map

[Amiya]

Hi Stephen,

Following http://stephen.genoprime.com/snippet/2020/03/28/snippet-7.html, insert of single vertex and batch of vertex works.

I am able to write edge creation between dynamic vertex as well. Below query works well.

l = [

[from: 'marko', to: 'josh', properties: [ weight: 9]]

];

g.inject(l).

unfold().as('edge').

addE('knows').

from(V().has('name', select('edge').select('from'))).

to(V().has('name', select('edge').select('to'))).

as('e').

sideEffect(select('edge').select('properties').

unfold().as('kv').

select('e').

property(select('kv').by(keys), select('kv').by(values)))

Then I tried to extend the query for insert/update vertex using coalesce, but the query did not work as expected.

When I try to debug I do not understand why filtering does not happen.

gremlin> l = [ 'josh']

gremlin> g.inject(l).unfold().as('n').V().has('name', select('n')).valueMap()

==>{name=[josh], age=[32], country=[usa]}

==>{name=[vadas], age=[27], country=[usa]}

==>{name=[marko], age=[29], country=[usa]}  // why all 3 vertices in result

gremlin> l = ['josh', 'marko']

==>josh

==>marko

gremlin> g.inject(l).unfold().as('n').V().has('name', select('n')).valueMap()

==>{name=[josh], age=[32], country=[usa]}

==>{name=[vadas], age=[27], country=[usa]}

==>{name=[marko], age=[29], country=[usa]}

==>{name=[josh], age=[32], country=[usa]}

==>{name=[vadas], age=[27], country=[usa]}

==>{name=[marko], age=[29], country=[usa]} // now all vertex repeat for each value in list ???

gremlin> g.inject(l).unfold().map{V().has('name', it.get()).next()}.valueMap()

gremlin> //no result


//I can get result if I start traversal from anonymous traversal and then use g.V() inside map() 

gremlin> inject(l).unfold().map{g.V().has('name', it.get()).next()}.valueMap()

==>{name=[josh], age=[32], country=[usa]}

==>{name=[marko], age=[29], country=[usa]}

gremlin> l = ['josh', 'amiya']

gremlin> inject(l).unfold().as('n').map{g.V().has('name', it.get()).fold().

......1>   coalesce(unfold(), addV('person').property('name', it.get())).next()}.valueMap()

==>{name=[josh], age=[32], country=[usa]}

==>{name=[amiya]}

gremlin> l = [[name:'josh',age:29,country:'usa'], [name:'foo',age:24,country:'usa']];

==>{name=josh, age=29, country=usa}

==>{name=foo, age=24, country=usa}

gremlin> inject(l).unfold().as('properties').map{g.V().has('name', it.get().get('name')).fold().

......1>   coalesce(unfold(), addV('person')).next()}.as('vertex').

......2> sideEffect(select('properties').

......3>               unfold().as('kv').

......4>               select('vertex').

......5>               property(select('kv').by(Column.keys), select('kv').by(Column.values)))

==>v[8192]

==>v[16384]

gremlin> g.V().valueMap(true)

==>{id=8192, label=person, name=[josh], age=[29], country=[usa]}

==>{id=12288, label=person, name=[vadas], age=[27], country=[usa]}

==>{id=16384, label=person, name=[foo], age=[24], country=[usa]}

==>{id=4312, label=person, name=[marko], age=[29], country=[usa]}

==>{id=20632, label=person, name=[amiya]}

 Though at last I get the the result, I have 2 concern

• it involves lambda -- not sugestible
• it involves g.V() in middle of step traversal -- so it would be treated as a single traversal or it is similar to the brute force way (vertices.each { v -> ....addV();}) 

Any better way to achieve this?

TIA,

Amiya

[Stephen Mallette]

The has(String,Traversal) overload doesn't do what you think it does.

https://issues.apache.org/jira/browse/TINKERPOP-1463

gremlin> g.inject(['josh']).unfold().as('n').V().has('name', where(eq('n')))
==>v[4]

--
You received this message because you are subscribed to the Google Groups "Gremlin-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to gremlin-user...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/gremlin-users/b257d118-4e27-40ef-921f-87308b54da70%40googlegroups.com.

[Amiya]

Ahh, I see.

Robert already mentioned query for this use case itself.

Combining both version of query.

l = [
  [name:'josh',age:29,country:'usa'],

  [name:'bar',age:24,country:'usa']];

 

g.inject(l).

 unfold().as('properties').

 select('name').as('pName').

 coalesce(V().has('name', where(eq('pName'))),

     addV('person')).as('vertex').

 sideEffect(select('properties').

              unfold().as('kv').

              select('vertex').

              property(select('kv').by(Column.keys), select('kv').by(Column.values)))

It works perfectly.

Thanks,

Amiya 

To unsubscribe from this group and stop receiving emails from it, send an email to gremli...@googlegroups.com.