add test caes for update and delete

btree.h

@@ -676,6 +676,8 @@ void *internal_create_new_root(table_t *table, uint32_t right_child_page_num)
     *node_parent(left_child) = table->root_page_num;
     *node_parent(right_child) = table->root_page_num;
 
+    // above code is the same as `create_new_root`
+
     // adjust its children's parent
     for (uint32_t idx = 0; idx < *internal_node_num_keys(left_child); idx++)
     {

docs/intro.md

@@ -95,7 +95,7 @@ The input to the front-end is a SQL query. the output is sqlite virtual machine
 - 实现 Linux Kernel 的侵入式容器（实现一个链表）。
   - 基于这个链表，实现一个操作 log 链表，然后支持 commit/rollback 等操作。
 - 支持 `commit` ：把内存中修改过的内容持久化到磁盘（目前是 `.exit` 的时候覆盖写入）
-- 支持 `delete` ：删除某个 `key` .
+- ✅ 支持 `delete` ：删除某个 `key` .
   - 目前的 `delete` 是伪删除。
   - 目前只是简单从 leaf node 中删除，不会调整 parent 指针，也不会重新调整 B+Tree 的结构。
   - 这意味着，即使某一行从表中删除，但它依旧会占用磁盘空间。

spec/main_spec.rb

@@ -152,6 +152,42 @@ def run_script(commands)
     ])
   end
 
+  it 'test udpate' do
+    n = 20
+    list = Array(1..n)
+    script = list.map do |i| "insert #{i} #{i} #{i}@sjtu.edu.cn" end
+    script += list.map do |i| "update #{i} #{i} #{i}" end
+    script << "select"
+    script << ".exit"
+    result = run_script(script)
+
+    expected_values = list.map do |i| "(#{i}, #{i}, #{i})" end
+    expected_values[0] = "tinydb > " + expected_values[0]
+    expected_values.append(
+      "total #{n} rows", "Executed.", "tinydb > "
+    )
+    # print(result.last(n+3))
+    expect(result.last(n+3)).to match_array(expected_values)
+  end
+
+  it 'test delete' do
+    n = 20
+    list = Array(1..n)
+    script = list.map do |i| "insert #{i} #{i} #{i}" end
+    script += list.find_all{|e| e % 2 == 0}.map do |i| "delete #{i}" end
+    script << "select"
+    script << ".exit"
+
+    result = run_script(script)
+
+    expected_values = list.find_all{|e| e % 2 != 0}.map do |i| "(#{i}, #{i}, #{i})" end
+    expected_values[0] = "tinydb > " + expected_values[0]
+    expected_values.append(
+      "total #{n / 2} rows", "Executed.", "tinydb > "
+    )
+    expect(result.last(n / 2 + 3)).to match_array(expected_values)
+  end
+
   # insert n rows (or with shuffle)
   def run_batch_insertion(n, need_shuffle)
     print("\n#{n} rows, ", "shuffle: #{need_shuffle} \n")