ZYM/BH-TicketSystem
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ready to write full split in put

Browse Source
This commit is contained in:
happyZYM
2024-04-28 02:53:53 +00:00
parent 87e19fb96c
commit 617b366d90
3 changed files with 279 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
bpt/include/bpt/bpt.hpp
View File

@ -1,6 +1,8 @@
#ifndef BPT_HPP
#define BPT_HPP
#include <algorithm>
#include <cassert>
#include <cstdio>
#include <cstring>
#include <shared_mutex>
#include <vector>
@ -18,7 +20,7 @@ class BPlusTreeIndexer {
typedef BPlusTreePage<KeyType> PageType;
typedef ActualDataType<KeyType> _ActualDataType;
typedef std::pair<KeyType, default_numeric_index_t> key_index_pair_t;
typedef std::pair<KeyType, b_plus_tree_value_index_t> value_type;
// typedef std::pair<KeyType, b_plus_tree_value_index_t> value_type;
private:
struct PositionSignType {
@ -44,7 +46,7 @@ class BPlusTreeIndexer {
while ((res.path.back().first.template As<PageType>()->data.page_status & PageStatusType::LEAF) == 0) {
default_numeric_index_t nxt_page_id;
in_page_key_count_t internal_id = res.path.back().second;
if (internal_id < res.path.back().first.template As<PageType>()->data.key_count)
if (internal_id < _ActualDataType::kMaxKeyCount)
nxt_page_id = res.path.back().first.template As<PageType>()->data.p_data[internal_id].second;
else
nxt_page_id = res.path.back().first.template As<PageType>()->data.p_n;
@ -56,10 +58,14 @@ class BPlusTreeIndexer {
next_page_guard.As<PageType>()->data.p_data;
res.path.push_back(std::make_pair(std::move(next_page_guard), nxt));
}
if (nxt == res.path.back().first.template As<PageType>()->data.key_count) res.is_end = true;
if (nxt == res.path.back().first.template As<PageType>()->data.key_count)
res.is_end = true;
else
res.is_end = false;
return res;
}
void InsertEntryAt(PositionSignType &pos, const KeyType &key, b_plus_tree_value_index_t value) {
fprintf(stderr, "_ActualDataType::kMaxKeyCount = %d\n", (int)_ActualDataType::kMaxKeyCount);
if (siz == 0) {
// special case for the first entry
BasicPageGuard new_page_guard = bpm->NewPageGuarded(&root_page_id);
@ -75,14 +81,71 @@ class BPlusTreeIndexer {
// case 1: the page has enough space
memmove(page_guard.template AsMut<PageType>()->data.p_data + pos.path.back().second + 1,
page_guard.template As<PageType>()->data.p_data + pos.path.back().second,
(page_guard.template As<PageType>()->data.key_count - pos.path.back().second) * sizeof(value_type));
(page_guard.template As<PageType>()->data.key_count - pos.path.back().second) * sizeof(key_index_pair_t));
page_guard.template AsMut<PageType>()->data.p_data[pos.path.back().second] = std::make_pair(key, value);
page_guard.template AsMut<PageType>()->data.key_count++;
fprintf(stderr, "page_guard.template As<PageType>()->data.key_count = %d\n",
(int)page_guard.template As<PageType>()->data.key_count);
++siz;
return;
}
// In our case, the tree is not too high, so we do not consider borrowing from siblings, we just split the page.
// We first construct a new page, and then move half of the keys to the new page.
// The check if we split the root page, we just handle it.
// Otherwise, what we need to do is modify the parent page, then "insert" a new key to the parent page
page_id_t new_page_id;
BasicPageGuard new_page_guard = bpm->NewPageGuarded(&new_page_id);
// Then move the last kMinNumberOfKeysForLeaf keys(including newly inserted) to the new page
new_page_guard.AsMut<PageType>()->data.page_status = PageStatusType::LEAF;
new_page_guard.AsMut<PageType>()->data.key_count = _ActualDataType::kMinNumberOfKeysForLeaf;
page_guard.template AsMut<PageType>()->data.key_count -= _ActualDataType::kMinNumberOfKeysForLeaf;
new_page_guard.AsMut<PageType>()->data.p_n = page_guard.template As<PageType>()->data.p_n;
page_guard.template AsMut<PageType>()->data.p_n = new_page_id;
if (pos.path.back().second <= _ActualDataType::kMaxKeyCount - _ActualDataType::kMinNumberOfKeysForLeaf) {
// the new key is in the first half
memmove(new_page_guard.template AsMut<PageType>()->data.p_data,
page_guard.template As<PageType>()->data.p_data + _ActualDataType::kMaxKeyCount -
_ActualDataType::kMinNumberOfKeysForLeaf,
_ActualDataType::kMinNumberOfKeysForLeaf * sizeof(key_index_pair_t));
memmove(page_guard.template AsMut<PageType>()->data.p_data + pos.path.back().second + 1,
page_guard.template As<PageType>()->data.p_data + pos.path.back().second,
(page_guard.template As<PageType>()->data.key_count - pos.path.back().second) * sizeof(key_index_pair_t));
page_guard.template AsMut<PageType>()->data.p_data[pos.path.back().second] = std::make_pair(key, value);
page_guard.template AsMut<PageType>()->data.key_count++;
} else {
// the new key is in the second half
memmove(
new_page_guard.template AsMut<PageType>()->data.p_data,
page_guard.template As<PageType>()->data.p_data + _ActualDataType::kMaxKeyCount -
_ActualDataType::kMinNumberOfKeysForLeaf + 1,
(pos.path.back().second - (_ActualDataType::kMaxKeyCount - _ActualDataType::kMinNumberOfKeysForLeaf + 1)) *
sizeof(key_index_pair_t));
new_page_guard.template AsMut<PageType>()
->data.p_data[pos.path.back().second -
(_ActualDataType::kMaxKeyCount - _ActualDataType::kMinNumberOfKeysForLeaf + 1)] =
std::make_pair(key, value);
memmove(new_page_guard.template AsMut<PageType>()->data.p_data + pos.path.back().second -
(_ActualDataType::kMaxKeyCount - _ActualDataType::kMinNumberOfKeysForLeaf + 1) + 1,
page_guard.template As<PageType>()->data.p_data + pos.path.back().second,
(_ActualDataType::kMaxKeyCount - pos.path.back().second) * sizeof(key_index_pair_t));
page_guard.template AsMut<PageType>()->data.key_count++;
}
if (page_guard.template As<PageType>()->data.page_status & PageStatusType::ROOT) {
// special case for the root page
page_guard.template AsMut<PageType>()->data.page_status &= ~PageStatusType::ROOT;
BasicPageGuard new_root_page_guard = bpm->NewPageGuarded(&root_page_id);
new_root_page_guard.AsMut<PageType>()->data.page_status = PageStatusType::ROOT;
new_root_page_guard.AsMut<PageType>()->data.key_count = 1;
new_root_page_guard.AsMut<PageType>()->data.p_data[0] = std::make_pair(
page_guard.template As<PageType>()->data.p_data[page_guard.template As<PageType>()->data.key_count - 1].first,
page_guard.PageId());
new_root_page_guard.AsMut<PageType>()->data.p_data[1] = std::make_pair(KeyType(), new_page_id);
++siz;
fprintf(stderr, "new_page_guard.AsMut<PageType>()->data.key_count = %d\n",
(int)new_page_guard.AsMut<PageType>()->data.key_count);
return;
}
throw std::runtime_error("Not implemented yet: InsertEntryAt");
// TODO
}
void RemoveEntryAt(PositionSignType &pos) {
if (siz == 1) {
@ -96,9 +159,10 @@ class BPlusTreeIndexer {
if (page_guard.template As<PageType>()->data.key_count > _ActualDataType::kMinNumberOfKeysForLeaf ||
(page_guard.template As<PageType>()->data.page_status & PageStatusType::ROOT) != 0) {
// case 1: the page has enough keys
memmove(page_guard.template AsMut<PageType>()->data.p_data + pos.path.back().second,
page_guard.template As<PageType>()->data.p_data + pos.path.back().second + 1,
(page_guard.template As<PageType>()->data.key_count - pos.path.back().second - 1) * sizeof(value_type));
memmove(
page_guard.template AsMut<PageType>()->data.p_data + pos.path.back().second,
page_guard.template As<PageType>()->data.p_data + pos.path.back().second + 1,
(page_guard.template As<PageType>()->data.key_count - pos.path.back().second - 1) * sizeof(key_index_pair_t));
page_guard.template AsMut<PageType>()->data.key_count--;
--siz;
return;