Struct WindowProjector 

pub struct WindowProjector;

Window function result projector.

Transforms SQL query results into GraphQL-compatible JSON format.

Implementations

impl WindowProjector

pub fn project( rows: Vec<HashMap<String, Value>>, _plan: &WindowExecutionPlan, ) -> Result<Value>

Project SQL window function results to GraphQL JSON.

Arguments

• rows - SQL result rows as HashMaps (column name → value)
• plan - Window execution plan (for metadata like aliases)

Errors

Currently infallible; reserved for future extension (e.g., type coercion failures).

Returns

GraphQL-compatible JSON array of objects

Example

// Requires: a WindowExecutionPlan built from compiled schema metadata.
// See: tests/integration/ for runnable examples.
use std::collections::HashMap;
use serde_json::json;

let mut row = HashMap::new();
row.insert("revenue".to_string(), json!(100.00));
row.insert("category".to_string(), json!("Electronics"));
row.insert("rank".to_string(), json!(1));
let rows = vec![row];
// let result = WindowProjector::project(rows, &plan)?;
// result: [{"revenue": 100.00, "category": "Electronics", "rank": 1}]

pub fn wrap_in_data_envelope(projected: Value, query_name: &str) -> Value

Wrap projected results in a GraphQL data envelope.

Arguments

• projected - The projected JSON value (array of objects)
• query_name - The GraphQL field name (e.g., “sales_window”)

Returns

Complete GraphQL response structure

Example

let projected = json!([{"rank": 1}, {"rank": 2}]);
let response = WindowProjector::wrap_in_data_envelope(projected, "sales_window");
// { "data": { "sales_window": [{"rank": 1}, {"rank": 2}] } }
assert!(response.get("data").is_some());