Neo4j - Set Clause


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Using Set clause, you can add new properties to an existing Node or Relationship, and also add or update existing Properties values.

In this chapter, we are going to discuss how to −

  • Set a property
  • Remove a property
  • Set multiple properties
  • Set a label on a node
  • Set multiple labels on a node

Setting a Property

Using the SET clause, you can create a new property in a node.

Syntax

Following is the syntax for setting a property.

MATCH (node:label{properties . . . . . . . . . . . . . . }) 
SET node.property = value 
RETURN node

Example

Before proceeding with the example, first create a node named Dhawan as shown below.

CREATE (Dhawan:player{name: "shikar Dhawan", YOB: 1985, POB: "Delhi"}) 

Following is a sample Cypher Query to create a property named “highestscore” with value “187”.

MATCH (Dhawan:player{name: "shikar Dhawan", YOB: 1985, POB: "Delhi"}) 
SET Dhawan.highestscore = 187 
RETURN Dhawan

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 screnshot.

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.

Match Player

Result

On executing, you will get the following result. Here you can observe that a property with a key-value pair highestscore/187 is created in the node named “Dhawan”.

Key Value

Removing a Property

You can remove an existing property by passing NULL as value to it.

Syntax

Following is the syntax of removing a property from a node using the SET clause.

MATCH (node:label {properties}) 
SET node.property = NULL 
RETURN node 

Example

Before proceeding with the example, first create a node “jadeja” as shown below.

Create (Jadeja:player {name: "Ravindra Jadeja", YOB: 1988, POB: "NavagamGhed"})

Following is a sample Cypher Query which removes the property named POB from this node using the SET clause as shown below.

MATCH (Jadeja:player {name: "Ravindra Jadeja", YOB: 1988, POB: "NavagamGhed"}) 
SET Jadeja.POB = NULL 
RETURN Jadeja 

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.

Remove property

Result

On executing, you will get the following result. Here you can observe that the variable named POB was deleted.

Deleted POB

Setting Multiple Properties

In the same way, you can create multiple properties in a node using the Set clause. To do so, you need to specify these key value pairs with commas.

Syntax

Following is the syntax to create multiple properties in a node using the SET clause.

MATCH (node:label {properties}) 
SET node.property1 = value, node.property2 = value 
RETURN node 

Example

Following is a sample Cypher Query which creates multiple properties in a node using the SET clause in Neo4j.

MATCH (Jadeja:player {name: "Ravindra Jadeja", YOB: 1988})  
SET Jadeja.POB: "NavagamGhed", Jadeja.HS = "90" 
RETURN Jadeja

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.

Multiple Properties

Result

On executing, you will get the following result. Here you can observe that properties named POB and HS were created.

Executing Properties

Setting a Label on a Node

You can set a label to an existing node using the SET clause.

Syntax

Following is the syntax to set a label to an existing node.

MATCH (n {properties . . . . . . . }) 
SET n :label 
RETURN n 

Example

Before proceeding with the example, first create a node “Anderson” as shown below.

CREATE (Anderson {name: "James Anderson", YOB: 1982, POB: "Burnely"})

Following is a sample Cypher Query to set a label on a node using the SET clause. This query adds the label “player” to the node Anderson and returns it.

MATCH (Anderson {name: "James Anderson", YOB: 1982, POB: "Burnely"}) 
SET Anderson: player 
RETURN Anderson 

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.

Label Node

Result

On executing, you will get the following result. Here you can observe that the label named “player” is added to the node.

Added Player

Setting Multiple Labels on a Node

You can set multiple labels to an existing node using the SET clause. Here you need to specify the labels by separating them with colons “:”.

Syntax

Following is the syntax to set multiple labels to an existing node using the SET clause.

MATCH (n {properties . . . . . . . }) 
SET n :label1:label2 
RETURN n 

Example

Before proceeding with the example, first create a node named “Ishant” as shown below.

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

Following is a sample Cypher Query used to create multiple labels on a node using the SET clause.

MATCH (Ishant {name: "Ishant Sharma", YOB: 1988, POB: "Delhi"}) 
SET Ishant: player:person 
RETURN 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.

Multi Label

Result

On executing, you will get the following result. Here you can observe that two labels - person and player – are added to the node named Ishant.

Ishant Player

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