Skip to main content

Column

clickhouse_native_client::column

Trait Column 

Source 
pub trait Column: Send + Sync {

Show 13 methods    // Required methods
    fn column_type(&self) -> &Type;
    fn size(&self) -> usize;
    fn clear(&mut self);
    fn reserve(&mut self, new_cap: usize);
    fn append_column(&mut self, other: ColumnRef) -> Result<()>;
    fn load_from_buffer(
        &mut self,
        buffer: &mut &[u8],
        rows: usize,
    ) -> Result<()>;
    fn save_to_buffer(&self, buffer: &mut BytesMut) -> Result<()>;
    fn clone_empty(&self) -> ColumnRef;
    fn slice(&self, begin: usize, len: usize) -> Result<ColumnRef>;
    fn as_any(&self) -> &dyn Any;
    fn as_any_mut(&mut self) -> &mut dyn Any;

    // Provided methods
    fn load_prefix(&mut self, _buffer: &mut &[u8], _rows: usize) -> Result<()> { ... }
    fn save_prefix(&self, _buffer: &mut BytesMut) -> Result<()> { ... }

}
Expand description

Base trait for all column types Note: We use byte buffers instead of generic readers/writers to make the trait dyn-compatible

Required Methods§

Source

fn column_type(&self) -> &Type

Get the type of this column

Source

fn size(&self) -> usize

Get the number of rows in this column

Source

fn clear(&mut self)

Clear all data from the column

Source

fn reserve(&mut self, new_cap: usize)

Reserve capacity for at least new_cap elements

Source

fn append_column(&mut self, other: ColumnRef) -> Result<()>

Append another column’s data to this column

Source

fn load_from_buffer(&mut self, buffer: &mut &[u8], rows: usize) -> Result<()>

Load column data from byte buffer

Source

fn save_to_buffer(&self, buffer: &mut BytesMut) -> Result<()>

Save column data to byte buffer

Source

fn clone_empty(&self) -> ColumnRef

Create an empty clone of this column (same type, no data)

Source

fn slice(&self, begin: usize, len: usize) -> Result<ColumnRef>

Create a slice of this column

Source

fn as_any(&self) -> &dyn Any

Downcast to a concrete column type

Source

fn as_any_mut(&mut self) -> &mut dyn Any

Downcast to a mutable concrete column type

Provided Methods§

Source

fn load_prefix(&mut self, _buffer: &mut &[u8], _rows: usize) -> Result<()>

Load column prefix from byte buffer (for types that need prefix data) Default implementation is a no-op. Override for types like LowCardinality. This matches C++ clickhouse-cpp’s LoadPrefix pattern.

Source

fn save_prefix(&self, _buffer: &mut BytesMut) -> Result<()>

Save column prefix to byte buffer (for types that need prefix data) Default implementation is a no-op. Override for types like LowCardinality, Array with special nested types. This matches C++ clickhouse-cpp’s SavePrefix pattern.

Implementors§