Struct mz_persist_types::dyn_struct::DynStructCfg

pub struct DynStructCfg {
    pub(crate) cols: Arc<Vec<(String, DataType, StatsFn)>>,
}

The schema of a “dynamic” columnar struct.

Here, dynamic is used to mean that, unlike most Data impls, the columnar schema of this type is not inferrable purely from the type. Instead, it needs supplementary crate::columnar::ColumnCfg.

This exists because, among other reasons, mz’s Row type does not declare the schema at the type level (as opposed to something like Row(u64, i32)).

TODO(parkmycar): Remove this and all DynStruct* friends once crate::columnar::Schema2 is fully flushed out.

Fields

cols: Arc<Vec<(String, DataType, StatsFn)>>

Trait Implementations

impl Clone for DynStructCfg

fn clone(&self) -> DynStructCfg

Returns a copy of the value.

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

Performs copy-assignment from source.

impl ColumnCfg<DynStruct> for DynStructCfg

fn as_type(&self) -> DataType

Returns the DataType for an instance of T with this configuration.

impl ColumnCfg<Option<DynStruct>> for DynStructCfg

fn as_type(&self) -> DataType

Returns the DataType for an instance of T with this configuration.

impl ColumnMut<DynStructCfg> for DynStructMut

fn new(cfg: &DynStructCfg) -> Self

Construct an empty instance of this type with the given configuration.

fn cfg(&self) -> &DynStructCfg

Returns the super::ColumnCfg for this column.

impl ColumnRef<DynStructCfg> for DynStructCol

fn cfg(&self) -> &DynStructCfg

Returns the super::ColumnCfg for this column.

fn len(&self) -> usize

Returns the number of elements in this column.

fn to_arrow(&self) -> Arc<dyn Array>

Returns this column as an arrow Array.

fn from_arrow(cfg: &DynStructCfg, array: &dyn Array) -> Result<Self, String>

Constructs the column from an arrow Array.

impl Debug for DynStructCfg

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

Formats the value using the given formatter.

impl From<Vec<(String, DataType, StatsFn)>> for DynStructCfg

fn from(value: Vec<(String, DataType, StatsFn)>) -> Self

Converts to this type from the input type.

impl PartialEq for DynStructCfg

fn eq(&self, other: &DynStructCfg) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for DynStructCfg