Struct datafusion::datasource::view::ViewTable

pub struct ViewTable { /* private fields */ }

An implementation of TableProvider that uses another logical plan.

Implementations

impl ViewTable

pub fn try_new(
    logical_plan: LogicalPlan,
    definition: Option<String>
) -> Result<Self>

Create new view that is executed at query runtime. Takes a LogicalPlan and an optional create statement as input.

Trait Implementations

impl TableProvider for ViewTable

fn as_any(&self) -> &dyn Any

Returns the table provider as Any so that it can be downcast to a specific implementation.

fn schema(&self) -> SchemaRef

Get a reference to the schema for this table

fn table_type(&self) -> TableType

Get the type of this table for metadata/catalog purposes.

fn get_table_definition(&self) -> Option<&str>

Get the create statement used to create this table, if available.

fn scan<'life0, 'life1, 'life2, 'life3, 'async_trait>(
    &'life0 self,
    ctx: &'life1 SessionState,
    _projection: &'life2 Option<Vec<usize>>,
    _filters: &'life3 [Expr],
    _limit: Option<usize>
) -> Pin<Box<dyn Future<Output = Result<Arc<dyn ExecutionPlan>>> + Send + 'async_trait>> where
    'life0: 'async_trait,
    'life1: 'async_trait,
    'life2: 'async_trait,
    'life3: 'async_trait,
    Self: 'async_trait, 

Create an ExecutionPlan that will scan the table. The table provider will be usually responsible of grouping the source data into partitions that can be efficiently parallelized or distributed.

fn supports_filter_pushdown(
    &self,
    _filter: &Expr
) -> Result<TableProviderFilterPushDown>

Tests whether the table provider can make use of a filter expression to optimise data retrieval.