Struct datafusion_physical_expr::expressions::TryCastExpr

pub struct TryCastExpr { /* private fields */ }

TRY_CAST expression casts an expression to a specific data type and retuns NULL on invalid cast

Implementations

impl TryCastExpr

pub fn new(expr: Arc<dyn PhysicalExpr>, cast_type: DataType) -> Self

Create a new CastExpr

pub fn expr(&self) -> &Arc<dyn PhysicalExpr>

The expression to cast

pub fn cast_type(&self) -> &DataType

The data type to cast to

Trait Implementations

impl Debug for TryCastExpr

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

Formats the value using the given formatter.

impl Display for TryCastExpr

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

Formats the value using the given formatter.

impl Hash for TryCastExpr

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq<dyn Any> for TryCastExpr

fn eq(&self, other: &dyn Any) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PhysicalExpr for TryCastExpr

fn as_any(&self) -> &dyn Any

Return a reference to Any that can be used for downcasting

fn data_type(&self, _input_schema: &Schema) -> Result<DataType>

Get the data type of this expression, given the schema of the input

fn nullable(&self, _input_schema: &Schema) -> Result<bool>

Determine whether this expression is nullable, given the schema of the input

fn evaluate(&self, batch: &RecordBatch) -> Result<ColumnarValue>

Evaluate an expression against a RecordBatch

fn children(&self) -> Vec<Arc<dyn PhysicalExpr>>

Get a list of child PhysicalExpr that provide the input for this expr.

fn with_new_children( self: Arc<Self>, children: Vec<Arc<dyn PhysicalExpr>> ) -> Result<Arc<dyn PhysicalExpr>>

Returns a new PhysicalExpr where all children were replaced by new exprs.

fn dyn_hash(&self, state: &mut dyn Hasher)

Update the hash state with this expression requirements from Hash.

fn evaluate_selection( &self, batch: &RecordBatch, selection: &BooleanArray ) -> Result<ColumnarValue>

Evaluate an expression against a RecordBatch after first applying a validity array

fn evaluate_bounds(&self, _children: &[&Interval]) -> Result<Interval>

Computes bounds for the expression using interval arithmetic.

fn propagate_constraints( &self, _interval: &Interval, _children: &[&Interval] ) -> Result<Vec<Option<Interval>>>

Updates/shrinks bounds for the expression using interval arithmetic. If constraint propagation reveals an infeasibility, returns None for the child causing infeasibility. If none of the children intervals change, may return an empty vector instead of cloning children.

fn get_ordering(&self, _children: &[SortProperties]) -> SortProperties

The order information of a PhysicalExpr can be estimated from its children. This is especially helpful for projection expressions. If we can ensure that the order of a PhysicalExpr to project matches with the order of SortExec, we can eliminate that SortExecs.