Struct datafusion::functions::string::concat_ws::ConcatWsFunc

pub struct ConcatWsFunc { /* private fields */ }

Implementations

impl ConcatWsFunc

pub fn new() -> ConcatWsFunc

Trait Implementations

impl Debug for ConcatWsFunc

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

Formats the value using the given formatter.

impl Default for ConcatWsFunc

fn default() -> ConcatWsFunc

Returns the “default value” for a type.

impl ScalarUDFImpl for ConcatWsFunc

fn invoke( &self, args: &[ColumnarValue] ) -> Result<ColumnarValue, DataFusionError>

Concatenates all but the first argument, with separators. The first argument is used as the separator string, and should not be NULL. Other NULL arguments are ignored. concat_ws(‘,’, ‘abcde’, 2, NULL, 22) = ‘abcde,2,22’

fn simplify( &self, args: Vec<Expr>, _info: &dyn SimplifyInfo ) -> Result<ExprSimplifyResult, DataFusionError>

Simply the concat_ws function by

1. folding to null if the delimiter is null
2. filtering out null arguments
3. using concat to replace concat_ws if the delimiter is an empty string
4. concatenating contiguous literals if the delimiter is a literal.

fn as_any(&self) -> &(dyn Any + 'static)

Returns this object as an Any trait object

fn name(&self) -> &str

Returns this function’s name

fn signature(&self) -> &Signature

Returns the function’s Signature for information about what input types are accepted and the function’s Volatility.

fn return_type( &self, _arg_types: &[DataType] ) -> Result<DataType, DataFusionError>

What DataType will be returned by this function, given the types of the arguments.

fn return_type_from_exprs( &self, _args: &[Expr], _schema: &dyn ExprSchema, arg_types: &[DataType] ) -> Result<DataType, DataFusionError>

What DataType will be returned by this function, given the arguments?

fn invoke_no_args( &self, _number_rows: usize ) -> Result<ColumnarValue, DataFusionError>

Invoke the function without args, instead the number of rows are provided, returning the appropriate result.

fn aliases(&self) -> &[String]

Returns any aliases (alternate names) for this function.

fn monotonicity(&self) -> Result<Option<Vec<Option<bool>>>, DataFusionError>

This function specifies monotonicity behaviors for User defined scalar functions.

fn short_circuits(&self) -> bool

Returns true if some of this exprs subexpressions may not be evaluated and thus any side effects (like divide by zero) may not be encountered Setting this to true prevents certain optimizations such as common subexpression elimination