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Neo4j – Delete Clause



You can delete nodes and relationships from a database using the DELETE clause.

Deleting All Nodes and Relationships

Following is the query to delete all the nodes and the relationships in the database using the DELETE clause.

Query

MATCH (n) DETACH DELETE n

To execute the above query, carry out the following steps −

Step 1 − Open the Neo4j desktop App and start the Neo4j Server. Open the built-in browser app of Neo4j using the URL http://localhost:7474/ as shown in the following screenshot.

Browser App

Step 2 − Copy and paste the desired query in the dollar prompt and press the play button (to execute the query) highlighted in the following screenshot.

Detach Match

This will delete all the nodes and relationships from your neo4j database and make it empty.

Deleting a Particular Node

To delete a particular node, you need to specify the details of the node in the place of “n” in the above query.

Syntax

Following is the syntax to delete a particular node from Neo4j using the DELETE clause.

MATCH (node:label {properties . . . . . . . . . .  }) 
DETACH DELETE node

Example

Before proceeding with the example, create a node “Ishant” in the Neo4j database as shown below.

CREATE (Ishant:player {name: "Ishant Sharma", YOB: 1988, POB: "Delhi"}) 

Following is a sample Cypher Query which deletes the above created node using the DELETE clause.

MATCH (Ishant:player {name: "Ishant Sharma", YOB: 1988, POB: "Delhi"}) 
DETACH DELETE Ishant

To execute the above query, carry out the following steps −

Step 1 − Open the Neo4j desktop App and start the Neo4j Server. Open the built-in browser app of Neo4j using the URL http://localhost:7474/ as shown in the following screenshot.

Browser App

Step 2 − Copy and paste the desired query in the dollar prompt and press the play button (to execute the query) highlighted in the following screenshot.

Particular Node

Result

On executing, you will get the following result. Here you can observe that the specified node is deleted.

Deleted Node

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