Struct TableSchemaBuilder 

pub struct TableSchemaBuilder { /* private fields */ }

Builder for TableSchema.

The file schema is the only required input; partition columns and virtual columns are optional. Unlike calling TableSchema’s setters repeatedly, the builder computes the concatenated table schema exactly once, in TableSchemaBuilder::build.

let table_schema = TableSchemaBuilder::new(file_schema)
    .with_table_partition_cols(vec![Arc::new(Field::new("date", DataType::Utf8, false))])
    .build();
assert_eq!(table_schema.table_partition_cols().len(), 1);

Implementations

impl TableSchemaBuilder

pub fn new(file_schema: SchemaRef) -> Self

Create a builder for a TableSchema over the given file schema, with no partition or virtual columns yet.

pub fn with_table_partition_cols( self, table_partition_cols: impl Into<Fields>, ) -> Self

Set the partition columns, replacing any previously set.

Accepts anything convertible into Fields (e.g. Vec<FieldRef> or an existing schema’s Fields, which is shared zero-copy).

pub fn with_virtual_columns(self, virtual_columns: impl Into<Fields>) -> Self

Set the virtual columns, replacing any previously set.

Virtual columns are produced by the file reader (e.g. Parquet row_number) and appended at the end of the table schema. Each field must carry an arrow virtual extension type so the reader can recognize it.

Accepts anything convertible into Fields (e.g. Vec<FieldRef>).

pub fn build(self) -> TableSchema

Build the TableSchema, computing the full file + partition + virtual schema once.

Trait Implementations

impl Clone for TableSchemaBuilder

fn clone(&self) -> TableSchemaBuilder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TableSchemaBuilder

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

Formats the value using the given formatter.

impl From<&Arc<Schema>> for TableSchemaBuilder

fn from(schema: &SchemaRef) -> Self

Converts to this type from the input type.

impl From<Arc<Schema>> for TableSchemaBuilder

fn from(schema: SchemaRef) -> Self

Converts to this type from the input type.