Struct TaskContext 

pub struct TaskContext { /* private fields */ }

Task Execution Context

A TaskContext contains the state required during a single query’s execution. Please see the documentation on SessionContext for more information.

Relationship with ExecutionProps

TaskContext is intentionally distinct from ExecutionProps. ExecutionProps is state used while optimizing a logical plan and constructing a physical plan.

TaskContext is the runtime context passed to physical operators when executing a physical plan. It carries runtime services and session state needed at that stage, such as RuntimeEnv, memory-pool access, session configuration, and function lookup.

Keeping these structures separate avoids threading execution/runtime state through planning APIs, and avoids making execution depend on planner-only scratch state.

Implementations

impl TaskContext

pub fn new( task_id: Option<String>, session_id: String, session_config: SessionConfig, scalar_functions: HashMap<String, Arc<ScalarUDF>>, higher_order_functions: HashMap<String, Arc<HigherOrderUDF>>, aggregate_functions: HashMap<String, Arc<AggregateUDF>>, window_functions: HashMap<String, Arc<WindowUDF>>, runtime: Arc<RuntimeEnv>, ) -> TaskContext

Create a new TaskContext instance.

Most users will use SessionContext::task_ctx to create TaskContexts

pub fn session_config(&self) -> &SessionConfig

Return the SessionConfig associated with this TaskContext

pub fn session_id(&self) -> String

Return the session_id of this TaskContext

pub fn task_id(&self) -> Option<String>

Return the task_id of this TaskContext

pub fn memory_pool(&self) -> &Arc<dyn MemoryPool>

Return the MemoryPool associated with this TaskContext

pub fn runtime_env(&self) -> Arc<RuntimeEnv>

Return the RuntimeEnv associated with this TaskContext

pub fn scalar_functions(&self) -> &HashMap<String, Arc<ScalarUDF>>

pub fn higher_order_functions(&self) -> &HashMap<String, Arc<HigherOrderUDF>>

pub fn aggregate_functions(&self) -> &HashMap<String, Arc<AggregateUDF>>

pub fn window_functions(&self) -> &HashMap<String, Arc<WindowUDF>>

pub fn with_session_config(self, session_config: SessionConfig) -> TaskContext

Update the SessionConfig

pub fn with_runtime(self, runtime: Arc<RuntimeEnv>) -> TaskContext

Update the RuntimeEnv

Trait Implementations

impl Debug for TaskContext

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

Formats the value using the given formatter.

impl Default for TaskContext

fn default() -> TaskContext

Returns the “default value” for a type.

impl From<&SessionContext> for TaskContext

Create a new task context instance from SessionContext

fn from(session: &SessionContext) -> Self

Converts to this type from the input type.

impl From<&SessionState> for TaskContext

Create a new task context instance from SessionState

fn from(state: &SessionState) -> Self

Converts to this type from the input type.

impl From<&dyn Session> for TaskContext

Create a new task context instance from Session

fn from(state: &dyn Session) -> TaskContext

Converts to this type from the input type.

impl FunctionRegistry for TaskContext

fn udfs(&self) -> HashSet<String>

Returns names of all available scalar user defined functions.

fn udf(&self, name: &str) -> Result<Arc<ScalarUDF>, DataFusionError>

Returns a reference to the user defined scalar function (udf) named name.

fn higher_order_function( &self, name: &str, ) -> Result<Arc<HigherOrderUDF>, DataFusionError>

Returns a reference to the user defined higher order function named name.

fn udaf(&self, name: &str) -> Result<Arc<AggregateUDF>, DataFusionError>

Returns a reference to the user defined aggregate function (udaf) named name.

fn udwf(&self, name: &str) -> Result<Arc<WindowUDF>, DataFusionError>

Returns a reference to the user defined window function (udwf) named name.

fn register_udaf( &mut self, udaf: Arc<AggregateUDF>, ) -> Result<Option<Arc<AggregateUDF>>, DataFusionError>

Registers a new AggregateUDF, returning any previously registered implementation.

fn register_udwf( &mut self, udwf: Arc<WindowUDF>, ) -> Result<Option<Arc<WindowUDF>>, DataFusionError>

Registers a new WindowUDF, returning any previously registered implementation.

fn register_udf( &mut self, udf: Arc<ScalarUDF>, ) -> Result<Option<Arc<ScalarUDF>>, DataFusionError>

Registers a new ScalarUDF, returning any previously registered implementation.

fn register_higher_order_function( &mut self, function: Arc<HigherOrderUDF>, ) -> Result<Option<Arc<HigherOrderUDF>>, DataFusionError>

Registers a new HigherOrderUDF, returning any previously registered implementation.

fn expr_planners(&self) -> Vec<Arc<dyn ExprPlanner>>

Set of all registered ExprPlanners

fn higher_order_function_names(&self) -> HashSet<String>

Returns names of all available higher order user defined functions.

fn udafs(&self) -> HashSet<String>

Returns names of all available aggregate user defined functions.

fn udwfs(&self) -> HashSet<String>

Returns names of all available window user defined functions.

fn deregister_udf( &mut self, _name: &str, ) -> Result<Option<Arc<ScalarUDF>>, DataFusionError>

Deregisters a ScalarUDF, returning the implementation that was deregistered.

fn deregister_higher_order_function( &mut self, _name: &str, ) -> Result<Option<Arc<HigherOrderUDF>>, DataFusionError>

Deregisters a HigherOrderUDF, returning the implementation that was deregistered.

fn deregister_udaf( &mut self, _name: &str, ) -> Result<Option<Arc<AggregateUDF>>, DataFusionError>

Deregisters a AggregateUDF, returning the implementation that was deregistered.

fn deregister_udwf( &mut self, _name: &str, ) -> Result<Option<Arc<WindowUDF>>, DataFusionError>

Deregisters a WindowUDF, returning the implementation that was deregistered.

fn register_function_rewrite( &mut self, _rewrite: Arc<dyn FunctionRewrite + Send + Sync>, ) -> Result<(), DataFusionError>

Registers a new FunctionRewrite with the registry.

fn register_expr_planner( &mut self, _expr_planner: Arc<dyn ExprPlanner>, ) -> Result<(), DataFusionError>

Registers a new ExprPlanner with the registry.