Struct tidb_query_executors::top_n_executor::HeapItemUnsafe

struct HeapItemUnsafe {
    order_is_desc_ptr: NonNull<[bool]>,
    order_exprs_field_type_ptr: NonNull<[FieldType]>,
    source_data: Arc<HeapItemSourceData>,
    eval_columns_buffer_ptr: NonNull<Vec<RpnStackNode<'static>>>,
    eval_columns_offset: usize,
    logical_row_index: usize,
}

The item in the heap of BatchTopNExecutor.

WARN: The content of this structure is valid only if BatchTopNExecutor is valid (i.e. not dropped). Thus it is called unsafe.

Fields

order_is_desc_ptr: NonNull<[bool]>

A pointer to the order_is_desc field in BatchTopNExecutor.

order_exprs_field_type_ptr: NonNull<[FieldType]>

A pointer to the order_exprs_field_type field in order_exprs.

source_data: Arc<HeapItemSourceData>

The source data that evaluated column in this structure is using.

eval_columns_buffer_ptr: NonNull<Vec<RpnStackNode<'static>>>

A pointer to the eval_columns_buffer field in BatchTopNExecutor.

eval_columns_offset: usize

The begin offset of the evaluated columns stored in the buffer.

The length of evaluated columns in the buffer is order_is_desc.len().

logical_row_index: usize

Which logical row in the evaluated columns this heap item is representing.

Implementations

impl HeapItemUnsafe

fn get_order_is_desc(&self) -> &[bool]

fn get_order_exprs_field_type(&self) -> &[FieldType]

fn get_eval_columns(&self, len: usize) -> &[RpnStackNode<'_>]

fn cmp_sort_key(&self, other: &Self) -> Result<Ordering>

Trait Implementations

impl Eq for HeapItemUnsafe

impl Ord for HeapItemUnsafe

WARN: HeapItemUnsafe implements partial ordering. It panics when Collator fails to parse. So make sure that it is valid before putting it into a heap.

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

#[must_use]pub fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]pub fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]pub fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<HeapItemUnsafe> for HeapItemUnsafe

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialOrd<HeapItemUnsafe> for HeapItemUnsafe

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]pub fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]pub fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]pub fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]pub fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.