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Schema

sqlglot_rust::schema

Trait Schema 

Source 
pub trait Schema {
    // Required methods
    fn add_table(
        &mut self,
        table_path: &[&str],
        columns: Vec<(String, DataType)>,
    ) -> Result<(), SchemaError>;
    fn column_names(
        &self,
        table_path: &[&str],
    ) -> Result<Vec<String>, SchemaError>;
    fn get_column_type(
        &self,
        table_path: &[&str],
        column: &str,
    ) -> Result<DataType, SchemaError>;
    fn has_column(&self, table_path: &[&str], column: &str) -> bool;
    fn dialect(&self) -> Dialect;

    // Provided method
    fn get_udf_type(&self, _name: &str) -> Option<&DataType> { ... }
}
Expand description

Schema trait for schema-aware analysis and optimization.

Provides methods to query table and column metadata. Implementations can back this with in-memory mappings, database catalogs, etc.

Required Methods§

Source

fn add_table( &mut self, table_path: &[&str], columns: Vec<(String, DataType)>, ) -> Result<(), SchemaError>

Register a table with its column definitions.

table_path is a slice of identifiers representing the fully qualified table path: [catalog, database, table], [database, table], or [table].

§Errors

Returns SchemaError::DuplicateTable if the table is already registered (use replace_table to overwrite).

Source

fn column_names(&self, table_path: &[&str]) -> Result<Vec<String>, SchemaError>

Get the column names for a table, in definition order.

§Errors

Returns SchemaError::TableNotFound if the table is not registered.

Source

fn get_column_type( &self, table_path: &[&str], column: &str, ) -> Result<DataType, SchemaError>

Get the data type of a specific column in a table.

§Errors

Returns SchemaError::TableNotFound or SchemaError::ColumnNotFound.

Source

fn has_column(&self, table_path: &[&str], column: &str) -> bool

Check whether a column exists in the given table.

Source

fn dialect(&self) -> Dialect

Get the dialect used for identifier normalization.

Provided Methods§

Source

fn get_udf_type(&self, _name: &str) -> Option<&DataType>

Get the return type of a registered UDF (user-defined function).

Returns None by default. Implementations that support UDFs should override this method.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§