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.
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
)
==== center ====
MATCH large_leaf<--center-->small_leaf
WHERE large_leaf.count = small_leaf.count + 1
CREATE small_leaf-[:X]->large_leaf
==== 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.
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
)
==== center ====
MATCH leaf1<--center-->leaf2
WHERE id(leaf1)<id(leaf2)
CREATE leaf1-[:X]->leaf2
==== 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 |
|
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.
Copyright © 2013 Neo Technology