How to set many properties to neo4j node with python bolt driver? - neo4j

How to do somethink like that:
data = {'field1': 'data1', 'field2': '#data2', 'field3': 'data3', 'field4': 'data4'}
r = session.run("MATCH (n) WHERE id(n) = 287 SET n = {props}", parameters=data)

You should also use a parameter for id
Otherwise using a dictionary for parameters works, not sure about kwargs
data = {'field1': 'data1', 'field2': '#data2', 'field3': 'data3', 'field4': 'data4'}
r = session.run("MATCH (n) WHERE id(n) = {id} SET n += {props}",
{'id':287, 'props':data})

Related

How to query with two conditions in Neo4j

I am new with Neo4j and I am stucked trying to get a query with two conditions, where I want to get all the "Autors" related to "Pixar" and "Fox". So far I have tried the following two ways:
MATCH (a:Autor)- [:AUTOR_DE]-> (t:Título) -[:PRODUCIDO_POR] ->( p:Productora {Nombre: "Pixar"}),
and
MATCH (a:Autor)- [:AUTOR_DE]-> (t:Título) -[:PRODUCIDO_POR] ->( p:Productora {Nombre: "Fox"}),
return a,p
and
MATCH (a:Autor)- [:AUTOR_DE]-> (t:Título) -[:PRODUCIDO_POR] ->( p:Productora)
WHERE ( (p:Productora) = "Fox" OR (p:Productora) = "Pixar")
return a,p
Thanks in advance
Assuming that a Productora node stores its name in a name property, and that every Productora node has a unique name, this should work:
MATCH (a:Autor)-[:AUTOR_DE]->(:Título)-[:PRODUCIDO_POR]->(p:Productora)
WHERE p.name = "Fox" OR p.name = "Pixar"
WITH a, COLLECT(DISTINCT p) AS ps
WHERE SIZE(ps) = 2
return a, ps
And this should also work:
MATCH (fox:Productora), (pixar:Productora), (a:Autor)
WHERE fox.name = "Fox" AND pixar.name = "Pixar" AND
(a)-[:AUTOR_DE]->(:Título)-[:PRODUCIDO_POR]->(fox) AND
(a)-[:AUTOR_DE]->(:Título)-[:PRODUCIDO_POR]->(pixar)
return a, fox, pixar

How to avoid duplications return distinct nodes and the relation ship using neo4j

I would like to return for a given node-id related nodes and their relationships props
For example:
-> defines a bi direction relationship with property timestamp
1234->777
777->1234
1234->999
999->1234
1234->888
888->1234
1234,777,888,999 are node-ids
When I execute this:
final PreparedStatement ps = conn.prepareStatement("start a = node(1234) match (a)-[k:nearby*]->(b) where a<>b return DISTINCT b, k");
ResultSet rs = ps.executeQuery();
while (rs.next()) {
Map result = (Map<String, Object>) rs.getObject("b");
System.out.println(result.toString());
}
} catch (SQLException e) {
e.printStackTrace();
logger.error("Error returning userId=" + userIdInput, e);
}
return null;
}
I get:
{userId=777}
{userId=999}
{userId=888}
{userId=888}
{userId=999}
{userId=999}
{userId=777}
{userId=888}
{userId=888}
{userId=777}
{userId=888}
{userId=777}
{userId=999}
{userId=999}
{userId=777}
How I do get distinct results only (777,888,999)
How to retrieve the relationship props of 1234 to the dest node? I expect to get the timestamp prop which defined on each relationship
Thank you,
ray.
I'm not sure what language you're using so I'll focus on the Cypher. Firstly I would replace the START query with a MATCH with a WHERE on ID(a):
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = 1234 AND a<>b
RETURN DISTINCT b, k
Secondly I'm pretty sure you don't need the a<>b because Cypher paths won't loop back on the same nodes:
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = 1234
RETURN DISTINCT b, k
Lastly, and to your question, I suspect the reason that you're getting duplicates is because you have multiple relationships. If so you can return the result node and an array of the relationships like so:
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = 1234
RETURN collect(b), k
That should return you node/relationship objects (with properties on both). Depending on your language/library you might get Maps or you might get objects wrapping the data
If your library doesn't return the start/end nodes for relationships for you, you can do something like this:
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = 1234
RETURN collect({rel: b, startnode: startnode(b), endnode: endnode(b)}), k
Hopefully that helps!
You get non distinct results, because you return both b and k
If you only want to get distinct b's use:
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = 1234 AND a<>b
RETURN DISTINCT b
You should also use parameters!
MATCH (a)-[k:nearby*]->(b)
WHERE ID(a) = {1} AND a<>b
RETURN DISTINCT b
ps.setInt(1,1234);

How to set enumeration on properties for selected nodes in one cypher statement?

My graph contains a set of nodes which are enumerated using a dedicated field fid. I want to update this enumeration periodically.
My current approach is to reset the enumeration and execute multiple statements that increase the fid for each node.
1. (f:File) set f.fid = -1
for(int i = 0; i < count ; i++) {
2. (f:File) set f.fid = i where id(f) = nodeId
}
I guess it should be possible to execute this task using a single cypher statement using the foreach clause.
MATCH p=(f:File)
FOREACH (n IN nodes(p)| SET f.fid = -1 )
I was looking for something similar to this statement.
MATCH (f:File)
WITH COLLECT(f) AS fs
WITH fs, i = 0
FOREACH (f in fs, i=i+1| SET f.fid = i ) return f.fid, f.name
Based on the following console set : http://console.neo4j.org/r/447qni
The following query seems to do the trick :
MATCH (f:File)
WITH collect(f) as f, count(f) AS c
UNWIND range(0,c-1) AS x
WITH f[x] AS file,x
SET file.iteration = x+1

Neo4j/Cypher: Setting a map and property yields "expected valid query body"

The following query fails:
MATCH n:User
WHERE n.email = "test"
SET n = {data}, n.created = timestamp()
RETURN n
Is this expected? Is it a bug? Is there a workaround? Do I have to compute the timestamp and send it along with {data}?
A slight modification of your statement using 2 SET clauses works:
MATCH n:User
WHERE n.email = "test"
SET n = {data}
SET n.created = timestamp()
RETURN n

How do I get list of nodes from calculated shortest path?

My Cypher looks like this:
START source=node(16822), target=node(12449)
MATCH p = allShortestPaths(source-[*]-target)
return p
And I want to write equivalent C# code for this. This is what I've come up till now
var query = client.Cypher
.Start(new { source = sourceNode.Reference, target = targetNode.Reference })
.Match("p = allShortestPaths(source-[*]-target)")
.Return<Node<Data>>("x");
Where Data is the class which has a string property(string ID).
What should i put in place of x to get my result as a list of concatenated IDs which comprises the path.
Cypher 2.0
START source=node(16822), target=node(12449)
MATCH p = allShortestPaths(source-[*]-target)
return nodes(p)
Good old way of executing query was the last resort which i used
CypherQuery query1 = new CypherQuery(#"START m=node(" + sourceNode.Reference.Id.ToString() + "), n=node(" + targetNode.Reference.Id.ToString() + #")
match p = allshortestpaths(m-[*]-n)
return distinct Extract(x in NODES(p): x.NodeId) as paths", paramCollection, CypherResultMode.Set);
var paths = ((IRawGraphClient)client).ExecuteGetCypherResults<List<string>>(query1);

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