Struct MappingSchema 

pub struct MappingSchema { /* private fields */ }

A mapping-based schema implementation

Supports nested schemas with different levels:

• Level 1: {table: {col: type}}
• Level 2: {db: {table: {col: type}}}
• Level 3: {catalog: {db: {table: {col: type}}}}

Implementations

impl MappingSchema

pub fn new() -> Self

Create a new empty schema

pub fn with_dialect(dialect: DialectType) -> Self

Create a schema with a specific dialect

pub fn without_normalization(self) -> Self

Create a schema with normalization disabled

pub fn set_visible_columns(&mut self, table: &str, columns: &[&str])

Set visibility for columns in a table

Trait Implementations

impl Clone for MappingSchema

fn clone(&self) -> MappingSchema

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MappingSchema

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

Formats the value using the given formatter.

impl Default for MappingSchema

fn default() -> Self

Returns the “default value” for a type.

impl Schema for MappingSchema

fn dialect(&self) -> Option<DialectType>

Get the dialect associated with this schema (if any)

fn add_table( &mut self, table: &str, columns: &[(String, DataType)], _dialect: Option<DialectType>, ) -> SchemaResult<()>

Add or update a table in the schema

fn column_names(&self, table: &str) -> SchemaResult<Vec<String>>

Get column names for a table

fn get_column_type(&self, table: &str, column: &str) -> SchemaResult<DataType>

Get the type of a column in a table

fn has_column(&self, table: &str, column: &str) -> bool

Check if a column exists in a table

fn supported_table_args(&self) -> &[&str]

Get supported table argument levels

fn is_empty(&self) -> bool

Check if the schema is empty

fn depth(&self) -> usize

Get the nesting depth of the schema