Query Structure

Basic Query Syntax

HelixQL is built to be declarative query language that uses a functional syntax to traverse the graph and vector data.

Here, we use Python to deliver the query payload to the HelixDB server as a Query object. It will then execute the Helix query.

Example Query Syntax:

QUERY query_name(param1: Type, param2: Type) =>
    result <- traversal_expression
    RETURN result

Helix Components:

• QUERY: Keyword to start a query definition
• query_name: Identifier for the query
• parameters: Input parameters in parentheses
• Type: Type of the parameter (e.g. String, I32, F64, Boolean, [Type] or schema Node/Edge)
• =>: Separates query header from body
• result: Result of the query
• <-: Assignment operator
• RETURN: Specifies output values

class query_name(Query):
    def __init__(self, param1: Type, param2: Type):
        super().__init__()
        self.param1 = param1
        self.param2 = param2
    
    def query(self) -> List[Payload]:
        return [{"param1": self.param1, "param2": self.param2}]
    
    def response(self, response):
        return response
 
#### Example ####
db.query(query_name("<param1>", "<param2>"))

Python Components:

• class: Defines a new class
• query_name: Identifier for the query
• Query: Base class for all queries
• __init__: Constructor for the class
• query: Sends the query payload
• response: Handles the response from the server