Struct MemorySchemaProvider 

pub struct MemorySchemaProvider {
    tables: DashMap<String, Arc<dyn TableProvider>>,
}

Simple in-memory implementation of a schema.

Fields

tables: DashMap<String, Arc<dyn TableProvider>>

Implementations

impl MemorySchemaProvider

pub fn new() -> MemorySchemaProvider

Instantiates a new MemorySchemaProvider with an empty collection of tables.

Trait Implementations

impl Debug for MemorySchemaProvider

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

Formats the value using the given formatter.

impl Default for MemorySchemaProvider

fn default() -> MemorySchemaProvider

Returns the “default value” for a type.

impl SchemaProvider for MemorySchemaProvider

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

Returns this SchemaProvider as Any so that it can be downcast to a specific implementation.

fn table_names(&self) -> Vec<String>

Retrieves the list of available table names in this schema.

fn table<'life0, 'life1, 'async_trait>( &'life0 self, name: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<Arc<dyn TableProvider>>, DataFusionError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, MemorySchemaProvider: 'async_trait,

Retrieves a specific table from the schema by name, if it exists, otherwise returns None.

fn register_table( &self, name: String, table: Arc<dyn TableProvider>, ) -> Result<Option<Arc<dyn TableProvider>>, DataFusionError>

If supported by the implementation, adds a new table named name to this schema.

fn deregister_table( &self, name: &str, ) -> Result<Option<Arc<dyn TableProvider>>, DataFusionError>

If supported by the implementation, removes the name table from this schema and returns the previously registered TableProvider, if any.

fn table_exist(&self, name: &str) -> bool

Returns true if table exist in the schema provider, false otherwise.

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

Returns the owner of the Schema, default is None. This value is reported as part of `information_tables.schemata

fn table_type<'life0, 'life1, 'async_trait>( &'life0 self, name: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<TableType>, DataFusionError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Retrieves the type of a specific table from the schema by name, if it exists, otherwise returns None. Implementations for which this operation is cheap but Self::table is expensive can override this to improve operations that only need the type, e.g. SELECT * FROM information_schema.tables.