Creating multiple nodes with mutating Cypher

[Michael Klishin]

I am trying to create multiple nodes with mutating Cypher. Neo4J isn't happy with my queries and returns 400s.

Some variations on my query that I have tried:

foreach(n in {xs} : CREATE {n})
foreach(n in {xs} : CREATE a = {n} RETURN n)

where xs is a list of maps. Is what I am trying to do possible with mutating Cypher?

The exception trace in the server log says

«string matching regex `(?i)\\bstart\\b' expected but `f' found\nUnfortunately, you have run into a syntax error that we don't have a nice message for.\nBy sending the query that produced this error to cyp...@neo4j.org, you'll save the\npuppies and get better error messages in our next release.»

I am more interested in learning if what I am doing is possible than saving puppies so I decided to ask here.

MK

[Michael Hunger]

Michael,

that functionality just made it into cypher the other day.

create n={p}
// where p is an iterable (array, collection) of maps.

So if you have the latest 1.8-SNAPSHOT you should be able to do it.
see http://docs.neo4j.org/chunked/snapshot/query-create.html#create-create-multiple-nodes-from-map

Cheers

Michael

[Michael Klishin]

Michael Hunger:

> create n={p}
> // where p is an iterable (array, collection) of maps.
>
> So if you have the latest 1.8-SNAPSHOT you should be able to do it.

Yes, I am able to create individual nodes with 1.8 M01 and was wondering about doing it for iterables.

Trying the line you've provided above, I get

«org.neo4j.cypher.CypherTypeException: Don't know how to extract parameters from this type: java.util.ArrayList»

back at

org.neo4j.cypher.internal.mutation.GraphElementPropertyFunctions$class.getMapFromExpression(UpdateAction.scala:85)

MK

[Michael Klishin]

Michael Hunger:

> if you have the latest 1.8-SNAPSHOT you should be able to do it.

I am using 1.8-M01. Should I be using snapshots?

MK

[Michael Hunger]

This functionality is not in M01 it just made it in yesterday, so if you need this, yes or you have to wait for M02.

Michael

[Michael Klishin]

Michael Hunger:

> So if you have the latest 1.8-SNAPSHOT you should be able to do it.
> see http://docs.neo4j.org/chunked/snapshot/query-create.html#create-create-multiple-nodes-from-map

I can confirm that it works with the snapshot version. Very nice!

MK

[Andres Taylor]

On Fri, May 4, 2012 at 10:12 PM, Michael Klishin <michael....@gmail.com> wrote:

Michael Hunger:

> This functionality is not in M01 it just made it in yesterday, so if you need this, yes or you have to wait for M02.

I see. neo4j.org downloads page suggests the most recent snapshot is from April. Is this true? should I build from
source then?

That's weird. We push out snapshot from our CI build. I just checked downloaded the Unix version, and it contains binaries produced a few hours ago. 

We'll check why the date on the page is wrong...

Andrés 

[Michael Klishin]

Michael Hunger:

> This functionality is not in M01 it just made it in yesterday, so if you need this, yes or you have to wait for M02.

I see. neo4j.org downloads page suggests the most recent snapshot is from April. Is this true? should I build from
source then?

https://skitch.com/michaelklishin/82y93/neo4j-worlds-leading-graph-database-download

MK