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Simple Remappings  

Sometimes, you may want to rename a property that is returned from a traversal. You can access properties of an item by using the name of the property as defined in the schema. 
::{new_name: property_name}
::{alias: _::{property}}
You can use the name directly, or if you want to be more explicit, or in cases where there may be name clashes, you can use the _:: operator.
When using the SDKs or curling the endpoint, the query name must match what is defined in the queries.hx file exactly.

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Example 1: Basic property remapping

QUERY GetUserWithAlias () =>
    users <- N<User>::RANGE(0, 5)
    RETURN users::{
        userID: ::ID,
        displayName: name
    }

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

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

users = [
    {"name": "Alice Johnson", "age": 25, "email": "alice@example.com"},
    {"name": "Bob Smith", "age": 30, "email": "bob@example.com"},
    {"name": "Charlie Brown", "age": 28, "email": "charlie@example.com"},
]

for user in users:
    client.query("CreateUser", user)

result = client.query("GetUserWithAlias", {})
print("Users with remapped properties:", result)

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Nested Mappings  

::|item_name|{
    field: item_name::traversal,
    nested_field: other::{
        property: item_name::ID,
        ..
    }
}
The important thing to note here, is that if we were to access the ID like we have shown previously: nested_field: ID. This ID would be the ID of the other item, not the item_name item due to the tighter scope.
When accessing properties in nested mappings, scope matters. Use the explicit item_name::property syntax to access properties from outer scopes to avoid ambiguity.

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Example 1: User posts with nested remappings

QUERY GetUserPosts (user_id: ID) =>
    user <- N<User>(user_id)
    posts <- user::Out<HasPost>
    RETURN user::|usr|{
        posts: posts::{
            postID: ID,
            creatorID: usr::ID,
            creatorName: usr::name,
            ..
        }
    }

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

QUERY CreatePost (user_id: ID, title: String, content: String) =>
    user <- N<User>(user_id)
    post <- AddN<Post>({
        title: title,
        content: content
    })
    AddE<HasPost>::From(user)::To(post)
    RETURN post
Here’s how to run the query using the SDKs or curl 
from helix.client import Client

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

user_result = client.query("CreateUser", {
    "name": "Alice Johnson",
    "age": 25,
    "email": "alice@example.com"
})
user_id = user_result[0]["user"]["id"]

posts = [
    {"title": "My First Post", "content": "This is my first blog post!"},
    {"title": "Learning GraphDB", "content": "Graph databases are fascinating."},
    {"title": "Weekend Plans", "content": "Planning to explore the city."},
]

for post in posts:
    client.query("CreatePost", {
        "user_id": user_id,
        "title": post["title"],
        "content": post["content"]
    })

result = client.query("GetUserPosts", {"user_id": user_id})
print("User posts with nested remappings:", result)