​
DROP

Drops elements from your database. The DROP effects the elements returned by the traversal. 
DROP <traversal>
You can use the drop on any traversal that returns a list of elements. DROP will do nothing if the result of the expression is not a list of elements or if the list is empty.

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Example 1: Removing a user node by ID

Dropping a node will also remove all related edges that are connected to it. 
QUERY DeleteUserNode (user_id: ID) =>
    DROP N<User>(user_id)
    RETURN "Removed user node"

QUERY CreateUser (name: String, age: U8, email: String) =>
    user <- AddN<User>({ name: name, age: age, email: email })
    RETURN user
Heres how to run the query using the SDKs or curl 
from helix.client import Client

client = Client(local=True, port=6969)

yara = client.query("CreateUser", {
    "name": "Yara",
    "age": 24,
    "email": "yara@example.com",
})
yara_id = yara[0]["user"]["id"]

result = client.query("DeleteUserNode", {"user_id": yara_id})
print(result)

​
Example 2: Removing outgoing neighbors

Use DROP on the outgoing traversal to delete connected neighbor nodes and the connecting edges. 
QUERY DeleteOutgoingNeighbors (user_id: ID) =>
    DROP N<User>(user_id)::Out<Follows>
    RETURN "Removed outgoing neighbors"

QUERY CreateUser (name: String, age: U8, email: String) =>
    user <- AddN<User>({ name: name, age: age, email: email })
    RETURN user

QUERY CreateRelationships (user1_id: ID, user2_id: ID) =>
    follows <- AddE<Follows>::From(user1_id)::To(user2_id)
    RETURN follows
Heres how to run the query using the SDKs or curl 
from helix.client import Client

client = Client(local=True, port=6969)

lena = client.query("CreateUser", {
    "name": "Lena",
    "age": 30,
    "email": "lena@example.com",
})
lena_id = lena[0]["user"]["id"]

mason = client.query("CreateUser", {
    "name": "Mason",
    "age": 29,
    "email": "mason@example.com",
})
mason_id = mason[0]["user"]["id"]

client.query("CreateRelationships", {
    "user1_id": lena_id,
    "user2_id": mason_id,
})

result = client.query("DeleteOutgoingNeighbors", {"user_id": lena_id})
print(result)

​
Example 3: Removing incoming neighbors

Delete any users that follow the target user by traversing incoming connections. 
QUERY DeleteIncomingNeighbors (user_id: ID) =>
    DROP N<User>(user_id)::In<Follows>
    RETURN "Removed incoming neighbors"

QUERY CreateUser (name: String, age: U8, email: String) =>
    user <- AddN<User>({ name: name, age: age, email: email })
    RETURN user

QUERY CreateRelationships (user1_id: ID, user2_id: ID) =>
    follows <- AddE<Follows>::From(user1_id)::To(user2_id)
    RETURN follows
Heres how to run the query using the SDKs or curl 
from helix.client import Client

client = Client(local=True, port=6969)

ophelia = client.query("CreateUser", {
    "name": "Ophelia",
    "age": 32,
    "email": "ophelia@example.com",
})
ophelia_id = ophelia[0]["user"]["id"]

paul = client.query("CreateUser", {
    "name": "Paul",
    "age": 31,
    "email": "paul@example.com",
})
paul_id = paul[0]["user"]["id"]

client.query("CreateRelationships", {
    "user1_id": paul_id,
    "user2_id": ophelia_id,
})

result = client.query("DeleteIncomingNeighbors", {"user_id": ophelia_id})
print(result)

​
Example 4: Removing outgoing edges only

Strip all follows edges that originate from the user without touching the neighbor nodes. 
QUERY DeleteOutgoingEdges (user_id: ID) =>
    DROP N<User>(user_id)::OutE<Follows>
    RETURN "Removed outgoing edges"

QUERY CreateUser (name: String, age: U8, email: String) =>
    user <- AddN<User>({ name: name, age: age, email: email })
    RETURN user

QUERY CreateRelationships (user1_id: ID, user2_id: ID) =>
    follows <- AddE<Follows>::From(user1_id)::To(user2_id)
    RETURN follows
Heres how to run the query using the SDKs or curl 
from helix.client import Client

client = Client(local=True, port=6969)

riley = client.query("CreateUser", {
    "name": "Riley",
    "age": 26,
    "email": "riley@example.com",
})
riley_id = riley[0]["user"]["id"]

sam = client.query("CreateUser", {
    "name": "Sam",
    "age": 25,
    "email": "sam@example.com",
})
sam_id = sam[0]["user"]["id"]

client.query("CreateRelationships", {
    "user1_id": riley_id,
    "user2_id": sam_id,
})

result = client.query("DeleteOutgoingEdges", {"user_id": riley_id})
print(result)

​
Example 5: Removing incoming edges only

Target follows edges pointing at the user while leaving the neighbor nodes untouched. 
QUERY DeleteIncomingEdges (user_id: ID) =>
    DROP N<User>(user_id)::InE<Follows>
    RETURN "Removed incoming edges"

QUERY CreateUser (name: String, age: U8, email: String) =>
    user <- AddN<User>({ name: name, age: age, email: email })
    RETURN user

QUERY CreateRelationships (user1_id: ID, user2_id: ID) =>
    follows <- AddE<Follows>::From(user1_id)::To(user2_id)
    RETURN follows
Heres how to run the query using the SDKs or curl 
from helix.client import Client

client = Client(local=True, port=6969)

uma = client.query("CreateUser", {
    "name": "Uma",
    "age": 28,
    "email": "uma@example.com",
})
uma_id = uma[0]["user"]["id"]

vince = client.query("CreateUser", {
    "name": "Vince",
    "age": 29,
    "email": "vince@example.com",
})
vince_id = vince[0]["user"]["id"]

client.query("CreateRelationships", {
    "user1_id": vince_id,
    "user2_id": uma_id,
})

result = client.query("DeleteIncomingEdges", {"user_id": uma_id})
print(result)
Currently, Helix does not support deleting vectors from the graph. As a workaround, you can delete the node and/or the edge that the vector is attached to.