Struct SchemaManager 

pub struct SchemaManager { /* private fields */ }

Manager for versioned table schema files.

Each table stores schema versions as JSON files under {table_path}/schema/schema-{id}. When a schema evolution occurs (e.g. ADD COLUMN, ALTER COLUMN TYPE), a new schema file is written with an incremented ID. Data files record which schema they were written with via DataFileMeta.schema_id.

The schema cache is shared across clones via Arc, so multiple readers (e.g. parallel split streams) benefit from a single cache.

Reference: org.apache.paimon.schema.SchemaManager

Implementations

impl SchemaManager

pub fn new(file_io: FileIO, table_path: String) -> Self

pub fn with_branch(&self, branch_name: &str) -> Self

Create a SchemaManager for a branch of this table.

pub fn schema_path(&self, schema_id: i64) -> String

Path to a specific schema file (e.g. {table_path}/schema/schema-0).

pub async fn list_all_ids(&self) -> Result<Vec<i64>>

List all schema ids sorted ascending. Returns an empty vector if the schema directory is missing or empty.

Mirrors Java SchemaManager.listAllIds().

pub async fn list_all(&self) -> Result<Vec<Arc<TableSchema>>>

List all schemas sorted by id ascending.

Mirrors Java SchemaManager.listAll().

pub async fn latest(&self) -> Result<Option<Arc<TableSchema>>>

Return the schema with the highest id, or None when no schema files exist under the schema directory.

Mirrors Java SchemaManager.latest().

pub async fn schema(&self, schema_id: i64) -> Result<Arc<TableSchema>>

Load a schema by ID. Returns cached version if available.

The cache is shared across all clones of this SchemaManager, so loading a schema in one stream makes it available to all other streams reading from the same table.

Reference: SchemaManager.schema(long)

Trait Implementations

impl Clone for SchemaManager

fn clone(&self) -> SchemaManager

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SchemaManager

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

Formats the value using the given formatter.