Struct LoadQuery 

pub struct LoadQuery {
    pub provider: Option<String>,
    pub params: HashMap<String, ValueWord>,
    pub target_type: Option<String>,
    pub column_mapping: Option<HashMap<String, String>>,
}

Generic data load request (industry-agnostic)

Supports arbitrary key-value parameters for maximum flexibility.

Examples

Finance:

LoadQuery {
    provider: Some("data"),
    params: { "symbol": "ES", "from": "2023-01-01", "to": "2023-12-31" },
    target_type: Some("Candle"),
}

Weather:

LoadQuery {
    provider: Some("weather_api"),
    params: { "station": "LAX", "metric": "temperature", "interval": "hourly" },
    target_type: Some("WeatherReading"),
}

Fields

provider: Option<String>

Provider name (e.g., “data”, “api”, “warehouse”) If None, uses default provider

params: HashMap<String, ValueWord>

Generic parameters (arbitrary key-value)

target_type: Option<String>

Target type name for validation (e.g., “Candle”, “TickData”) If specified, validates DataFrame has required columns

column_mapping: Option<HashMap<String, String>>

Optional column mapping override Maps: target_field → source_column

Implementations

impl LoadQuery

pub fn new() -> Self

Create a new empty load query

pub fn with_provider(self, name: &str) -> Self

Set provider name

pub fn with_param(self, key: &str, value: ValueWord) -> Self

Add a parameter

pub fn with_type(self, type_name: &str) -> Self

Set target type for validation

pub fn with_column_mapping(self, mapping: HashMap<String, String>) -> Self

Set column mapping

pub fn to_data_query(&self) -> Result<DataQuery>

Convert to provider-specific DataQuery

Extracts common parameters and builds a DataQuery. Provider-specific logic for parameter interpretation.

Errors

Returns error if required parameters are missing.

Trait Implementations

impl Clone for LoadQuery

fn clone(&self) -> LoadQuery

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LoadQuery

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for LoadQuery

fn default() -> Self

Returns the “default value” for a type.