Creating graph elements — nodes and relationships, is done with CREATE.
| Tip | |
|---|---|
In the |
Creating a single node is done by issuing the following query.
Query.
CREATE n
Nothing is returned from this query, except the count of affected nodes.
Creating a single node is done by issuing the following query.
Query.
CREATE (a {name : 'Andres'})
RETURN a
The newly created node is returned.
The values for the properties can be any scalar expressions.
| Caution | |
|---|---|
This syntax has been deprecated, please use the one in Section 13.1.2, “Return created node”. |
Query.
CREATE n = {name : 'Andres', title : 'Developer'}
Nothing is returned from this query.
To create a relationship between two nodes, we first get the two nodes. Once the nodes are loaded, we simply create a relationship between them.
Query.
START a=node(1), b=node(2) CREATE a-[r:RELTYPE]->b RETURN r
The created relationship is returned by the query.
Setting properties on relationships is done in a similar manner to how it’s done when creating nodes. Note that the values can be any expression.
Query.
START a=node(1), b=node(2)
CREATE a-[r:RELTYPE {name : a.name + '<->' + b.name }]->b
RETURN r
The newly created relationship is returned by the example query.
When you use CREATE and a pattern, all parts of the pattern that are not already in scope at this time
will be created.
Query.
CREATE p = (andres {name:'Andres'})-[:WORKS_AT]->neo<-[:WORKS_AT]-(michael {name:'Michael'})
RETURN p
This query creates three nodes and two relationships in one go, assigns it to a path identifier, and returns it.
Result
| p |
|---|
| 1 row |
| Nodes created: 3 |
| Relationships created: 2 |
| Properties set: 2 |
|
You can also create a graph entity from a Map<String,Object> map. All
the key/value pairs in the map will be set as properties on the created
relationship or node.
Query.
create ({props})
This query can be used in the following fashion:
Map<String, Object> props = new HashMap<String, Object>();
props.put( "name", "Andres" );
props.put( "position", "Developer" );
Map<String, Object> params = new HashMap<String, Object>();
params.put( "props", props );
engine.execute( "create ({props})", params );
By providing an iterable of maps (Iterable<Map<String,Object>>), Cypher will create a node for each map
in the iterable. When you do this, you can’t create anything else in the same create statement.
Query.
create (n {props}) return n
This query can be used in the following fashion:
Map<String, Object> n1 = new HashMap<String, Object>();
n1.put( "name", "Andres" );
n1.put( "position", "Developer" );
Map<String, Object> n2 = new HashMap<String, Object>();
n2.put( "name", "Michael" );
n2.put( "position", "Developer" );
Map<String, Object> params = new HashMap<String, Object>();
List<Map<String, Object>> maps = Arrays.asList( n1, n2 );
params.put( "props", maps );
engine.execute( "create (n {props}) return n", params );
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