Delete a Relationship
In Neo4j, a relationship can be deleted using the DELETE clause in Cypher Query Language (CQL). This can be useful when you want to remove a relationship between two nodes in your graph database.
Syntax
The syntax for deleting a relationship in Neo4j using CQL is as follows:
MATCH (node1)-[relationship]->(node2)
DELETE relationship
Where:
node1andnode2are the nodes that are connected by the relationship you want to delete.relationshipis the relationship type that you want to delete.
Example
Consider the following example graph:
Suppose we want to delete the FRIEND relationship between nodes A and B. We can use the following CQL query:
MATCH (A)-[r:FRIEND]->(B)
DELETE r
This will delete the FRIEND relationship between nodes A and B.
Output
The output of the query will not display anything. Instead, it will simply delete the specified relationship.
Explanation
In the example above, we used the MATCH clause to find the relationship we want to delete between nodes A and B. We then used the DELETE clause to remove the relationship from the graph.
Use
Deleting a relationship in Neo4j is useful when you want to remove a relationship between two nodes in your graph database. This can be helpful when you want to update the relationship between two nodes or remove old or irrelevant data from your graph database.
Important Points
- Before deleting a relationship, make sure you have identified the correct nodes and relationship type.
- Deleting a relationship will not delete any nodes in your graph database.
- Deleting a relationship will affect any queries that rely on that relationship.
Summary
In Neo4j, a relationship can be deleted using the DELETE clause in CQL. By specifying the two nodes and relationship type, you can remove a relationship from your graph database. This is useful when you want to update or remove old or irrelevant data from your graph. However, it is important to double-check your query as deleting a relationship can have an impact on any queries that rely on it.