Struct BTreeInternalPage 

pub struct BTreeInternalPage { /* private fields */ }

The internal page is used to store the keys and the page id of the children.

Binary Layout

• 4 bytes: page category
• 4 bytes: parent page index
• 4 bytes: children category (leaf/internal)
• n bytes: header bytes, indicate whether every slot of the page is used or not.
• n bytes: keys
• n bytes: children

Stable Criteria

count(used_slots) >= floor_dev(slot_count, 2)

Implementations

impl BTreeInternalPage

pub fn get_coresponding_entry( &self, left_pid: Option<&BTreePageID>, right_pid: Option<&BTreePageID>, ) -> Option<Entry>

pub fn stable(&self) -> bool

pub fn get_entry(&self, index: usize) -> Option<Entry>

pub fn delete_key_and_right_child(&mut self, record_id: usize)

pub fn delete_key_and_left_child(&mut self, record_id: usize)

pub fn update_entry(&mut self, entry: &Entry)

pub fn is_slot_used(&self, slot_index: usize) -> bool

Returns true if associated slot on this page is filled.

pub fn get_child_pid(&self, _index: usize) -> Option<BTreePageID>

pub fn get_first_child_pid(&self) -> BTreePageID

pub fn get_last_child_pid(&self) -> BTreePageID

pub fn get_left_sibling_pid(&self, tx: &Transaction) -> Option<BTreePageID>

pub fn get_right_sibling_pid(&self, tx: &Transaction) -> Option<BTreePageID>

pub fn get_entry_by_children( &self, left_pid: &BTreePageID, right_pid: &BTreePageID, ) -> Option<Entry>

pub fn check_integrity( &self, parent_pid: &BTreePageID, lower_bound: Option<IntField>, upper_bound: Option<IntField>, check_occupancy: bool, depth: usize, )

impl BTreeInternalPage

pub fn insert_entry(&mut self, e: &Entry) -> SmallResult

impl BTreeInternalPage

pub fn empty_slots_count(&self) -> usize

Empty slots (entries/children) count.

pub fn children_count(&self) -> usize

pub fn entries_count(&self) -> usize

impl BTreeInternalPage

pub fn get_children_capacity(&self) -> usize

pub fn get_stable_threshold(key_size: usize) -> usize

Retrive the minimum number of children needed to keep this page stable.

pub fn get_children_cap(key_size: usize) -> usize

Retrieve the maximum number of children this page can hold.

Trait Implementations

impl BTreePage for BTreeInternalPage

fn new( pid: &BTreePageID, bytes: &[u8], tuple_scheme: &Schema, key_field: usize, ) -> Self

fn get_pid(&self) -> BTreePageID

fn get_parent_pid(&self) -> BTreePageID

fn set_parent_pid(&mut self, pid: &BTreePageID)

fn get_page_data(&self) -> Vec<u8>

Generates a byte array representing the contents of this page. Used to serialize this page to disk.

fn set_before_image(&mut self)

fn get_before_image(&self) -> Vec<u8>

Provide a representation of this page before any modifications were made to it. Used by recovery.

fn peek(&self)