This section is showing how to create some of the named pretty graphs on Wikipedia.
The graph is created by first creating a center node, and then once per element in the range, creates a leaf node and connects it to the center.
Query.
CREATE (center) FOREACH (x IN range(1,6)| CREATE (leaf),(center)-[:X]->(leaf)) RETURN id(center) AS id;
The query returns the id of the center node.
Try this query live. (0) create (center) foreach( x in range(1,6) | create (leaf), (center)-[:X]->(leaf) ) return id(center) as id;
This graph is created in a number of steps:
Query.
CREATE (center) FOREACH (x IN range(1,6)| CREATE (leaf { count:x }),(center)-[:X]->(leaf)) WITH center MATCH (large_leaf)<--(center)-->(small_leaf) WHERE large_leaf.count = small_leaf.count + 1 CREATE (small_leaf)-[:X]->(large_leaf) WITH center, min(small_leaf.count) AS min, max(large_leaf.count) AS max MATCH (first_leaf)<--(center)-->(last_leaf) WHERE first_leaf.count = min AND last_leaf.count = max CREATE (last_leaf)-[:X]->(first_leaf) RETURN id(center) AS id
The query returns the id of the center node.
Try this query live. (0) CREATE (center) foreach( x in range(1,6) | CREATE (leaf {count:x}), (center)-[:X]->(leaf) ) WITH center MATCH (large_leaf)<--(center)-->(small_leaf) WHERE large_leaf.count = small_leaf.count + 1 CREATE (small_leaf)-[:X]->(large_leaf) WITH center, min(small_leaf.count) as min, max(large_leaf.count) as max MATCH (first_leaf)<--(center)-->(last_leaf) WHERE first_leaf.count = min AND last_leaf.count = max CREATE (last_leaf)-[:X]->(first_leaf) RETURN id(center) as id
For this graph, a root node is created, and used to hang a number of nodes from. Then, two nodes are selected, hanging from the center, with the requirement that the id of the first is less than the id of the next. This is to prevent double relationships and self relationships. Using said match, relationships between all these nodes are created. Lastly, the center node and all relationships connected to it are removed.
Query.
CREATE (center) FOREACH (x IN range(1,6)| CREATE (leaf { count : x }),(center)-[:X]->(leaf)) WITH center MATCH (leaf1)<--(center)-->(leaf2) WHERE id(leaf1)<id(leaf2) CREATE (leaf1)-[:X]->(leaf2) WITH center MATCH (center)-[r]->() DELETE center,r;
Nothing is returned by this query.
Result
Nodes created: 7 |
---|
Relationships created: 21 |
Properties set: 6 |
Nodes deleted: 1 |
Relationships deleted: 6 |
|
Try this query live. (0) create (center) foreach( x in range(1,6) | create (leaf {count : x}), (center)-[:X]->(leaf) ) WITH center MATCH (leaf1)<--(center)-->(leaf2) WHERE id(leaf1)<id(leaf2) CREATE (leaf1)-[:X]->(leaf2) WITH center MATCH (center)-[r]->() DELETE center,r;
This query first creates a center node, and then once per element in the range, creates a cycle graph and connects it to the center
Query.
CREATE (center) FOREACH (x IN range(1,3)| CREATE (leaf1),(leaf2),(center)-[:X]->(leaf1),(center)-[:X]->(leaf2), (leaf1)-[:X]->(leaf2)) RETURN ID(center) AS id
The id of the center node is returned by the query.
Try this query live. (0) CREATE (center) foreach( x in range(1,3) | CREATE (leaf1), (leaf2), (center)-[:X]->(leaf1), (center)-[:X]->(leaf2), (leaf1)-[:X]->(leaf2) ) RETURN ID(center) as id
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