Trait datafusion::catalog::schema::SchemaProvider

pub trait SchemaProvider: Sync + Send {
    fn as_any(&self) -> &dyn Any;
    fn table_names(&self) -> Vec<String>;
    fn table(&self, name: &str) -> Option<Arc<dyn TableProvider>>;
    fn table_exist(&self, name: &str) -> bool;

    fn register_table(
        &self,
        name: String,
        table: Arc<dyn TableProvider>
    ) -> Result<Option<Arc<dyn TableProvider>>> { ... }
    fn deregister_table(
        &self,
        name: &str
    ) -> Result<Option<Arc<dyn TableProvider>>> { ... }
}

Represents a schema, comprising a number of named tables.

Required Methods

fn as_any(&self) -> &dyn Any

Returns the schema provider 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(&self, name: &str) -> Option<Arc<dyn TableProvider>>

Retrieves a specific table from the schema by name, provided it exists.

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

If supported by the implementation, checks the table exist in the schema provider or not. If no matched table in the schema provider, return false. Otherwise, return true.

Provided Methods

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

If supported by the implementation, adds a new table to this schema. If a table of the same name existed before, it returns “Table already exists” error.

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

If supported by the implementation, removes an existing table from this schema and returns it. If no table of that name exists, returns Ok(None).

Implementors

impl SchemaProvider for MemorySchemaProvider