Coursework 2026

src/observer/common/type/attr_type.cpp

@@ -12,7 +12,7 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "common/type/attr_type.h"
 
-const char *ATTR_TYPE_NAME[] = {"undefined", "chars", "ints", "floats", "vectors", "booleans"};
+const char *ATTR_TYPE_NAME[] = {"undefined", "chars", "ints", "floats", "vectors", "booleans", "dates"};
 
 const char *attr_type_to_string(AttrType type)
 {
@@ -40,4 +40,4 @@ bool is_numerical_type(AttrType type)
 bool is_string_type(AttrType type)
 {
   return (type == AttrType::CHARS);
-}
+}

src/observer/common/type/attr_type.h

@@ -22,6 +22,7 @@ enum class AttrType
   FLOATS,    ///< 浮点数类型(4字节)
   VECTORS,   ///< 向量类型
   BOOLEANS,  ///< boolean类型，当前不是由parser解析出来的，是程序内部使用的
+  DATES,     ///< 日期类型(4字节，按YYYYMMDD编码)
   MAXTYPE,   ///< 请在 UNDEFINED 与 MAXTYPE 之间增加新类型
 };
 

src/observer/common/type/char_type.cpp

@@ -29,6 +29,8 @@ RC CharType::set_value_from_str(Value &val, const string &data) const
 RC CharType::cast_to(const Value &val, AttrType type, Value &result) const
 {
   switch (type) {
+    case AttrType::DATES:
+      return DataType::type_instance(AttrType::DATES)->set_value_from_str(result, val.get_string());
     default: return RC::UNIMPLEMENTED;
   }
   return RC::SUCCESS;
@@ -38,6 +40,8 @@ int CharType::cast_cost(AttrType type)
 {
   if (type == AttrType::CHARS) {
     return 0;
+  } else if (type == AttrType::DATES) {
+    return 1;
   }
   return INT32_MAX;
 }
@@ -48,4 +52,4 @@ RC CharType::to_string(const Value &val, string &result) const
   ss << val.value_.pointer_value_;
   result = ss.str();
   return RC::SUCCESS;
-}
+}

src/observer/common/type/data_type.cpp

@@ -9,6 +9,7 @@ MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 See the Mulan PSL v2 for more details. */
 
 #include "common/type/char_type.h"
+#include "common/type/date_type.h"
 #include "common/type/float_type.h"
 #include "common/type/integer_type.h"
 #include "common/type/data_type.h"
@@ -24,4 +25,5 @@ array<unique_ptr<DataType>, static_cast<int>(AttrType::MAXTYPE)> DataType::type_
     make_unique<FloatType>(),
     make_unique<VectorType>(),
     make_unique<DataType>(AttrType::BOOLEANS),
-};
+    make_unique<DateType>(),
+};

src/observer/common/type/date_type.cpp

@@ -0,0 +1,97 @@
+/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
+miniob is licensed under Mulan PSL v2.
+You can use this software according to the terms and conditions of the Mulan PSL v2.
+You may obtain a copy of Mulan PSL v2 at:
+         http://license.coscl.org.cn/MulanPSL2
+THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+See the Mulan PSL v2 for more details. */
+
+#include "common/type/date_type.h"
+
+#include <cstdio>
+#include <algorithm>
+#include <cctype>
+
+#include "common/lang/comparator.h"
+#include "common/value.h"
+#include "storage/common/column.h"
+
+RC DateType::parse_date(const string &text, int &encoded_date)
+{
+  const size_t first_dash = text.find('-');
+  const size_t second_dash = first_dash == string::npos ? string::npos : text.find('-', first_dash + 1);
+  if (first_dash != 4 || second_dash == string::npos || text.find('-', second_dash + 1) != string::npos ||
+      second_dash - first_dash < 2 || second_dash - first_dash > 3 ||
+      text.size() - second_dash < 2 || text.size() - second_dash > 3) {
+    return RC::SCHEMA_FIELD_TYPE_MISMATCH;
+  }
+
+  const auto all_digits = [](const string &part) {
+    return !part.empty() && std::all_of(part.begin(), part.end(), [](unsigned char ch) { return std::isdigit(ch); });
+  };
+  const string year_text = text.substr(0, first_dash);
+  const string month_text = text.substr(first_dash + 1, second_dash - first_dash - 1);
+  const string day_text = text.substr(second_dash + 1);
+  if (!all_digits(year_text) || !all_digits(month_text) || !all_digits(day_text)) {
+    return RC::SCHEMA_FIELD_TYPE_MISMATCH;
+  }
+
+  const int year = stoi(year_text);
+  const int month = stoi(month_text);
+  const int day = stoi(day_text);
+  if (year < 1 || month < 1 || month > 12) {
+    return RC::SCHEMA_FIELD_TYPE_MISMATCH;
+  }
+
+  static constexpr int DAYS_PER_MONTH[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+  int max_day = DAYS_PER_MONTH[month - 1];
+  const bool leap_year = (year % 4 == 0 && year % 100 != 0) || year % 400 == 0;
+  if (month == 2 && leap_year) {
+    max_day = 29;
+  }
+  if (day < 1 || day > max_day) {
+    return RC::SCHEMA_FIELD_TYPE_MISMATCH;
+  }
+
+  encoded_date = year * 10000 + month * 100 + day;
+  return RC::SUCCESS;
+}
+
+int DateType::compare(const Value &left, const Value &right) const
+{
+  ASSERT(left.attr_type() == AttrType::DATES && right.attr_type() == AttrType::DATES, "invalid date type");
+  int left_date = left.get_int();
+  int right_date = right.get_int();
+  return common::compare_int(&left_date, &right_date);
+}
+
+int DateType::compare(const Column &left, const Column &right, int left_idx, int right_idx) const
+{
+  ASSERT(left.attr_type() == AttrType::DATES && right.attr_type() == AttrType::DATES, "invalid date column type");
+  return common::compare_int(
+      (void *)&((int *)left.data())[left_idx], (void *)&((int *)right.data())[right_idx]);
+}
+
+RC DateType::to_string(const Value &val, string &result) const
+{
+  const int encoded_date = val.get_int();
+  const int year = encoded_date / 10000;
+  const int month = encoded_date / 100 % 100;
+  const int day = encoded_date % 100;
+  char buffer[16];
+  snprintf(buffer, sizeof(buffer), "%04d-%02d-%02d", year, month, day);
+  result = buffer;
+  return RC::SUCCESS;
+}
+
+RC DateType::set_value_from_str(Value &val, const string &data) const
+{
+  int encoded_date = 0;
+  RC rc = parse_date(data, encoded_date);
+  if (OB_SUCC(rc)) {
+    val.set_date(encoded_date);
+  }
+  return rc;
+}

src/observer/common/type/date_type.h

@@ -0,0 +1,27 @@
+/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
+miniob is licensed under Mulan PSL v2.
+You can use this software according to the terms and conditions of the Mulan PSL v2.
+You may obtain a copy of Mulan PSL v2 at:
+         http://license.coscl.org.cn/MulanPSL2
+THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+See the Mulan PSL v2 for more details. */
+
+#pragma once
+
+#include "common/type/data_type.h"
+
+class DateType : public DataType
+{
+public:
+  DateType() : DataType(AttrType::DATES) {}
+  ~DateType() override = default;
+
+  int compare(const Value &left, const Value &right) const override;
+  int compare(const Column &left, const Column &right, int left_idx, int right_idx) const override;
+  RC  to_string(const Value &val, string &result) const override;
+  RC  set_value_from_str(Value &val, const string &data) const override;
+
+  static RC parse_date(const string &text, int &encoded_date);
+};

src/observer/common/value.cpp

@@ -113,6 +113,10 @@ void Value::reset()
 void Value::set_data(char *data, int length)
 {
   switch (attr_type_) {
+    case AttrType::DATES: {
+      value_.int_value_ = *(int *)data;
+      length_           = length;
+    } break;
     case AttrType::CHARS: {
       set_string(data, length);
     } break;
@@ -149,6 +153,13 @@ void Value::set_float(float val)
   value_.float_value_ = val;
   length_             = sizeof(val);
 }
+void Value::set_date(int val)
+{
+  reset();
+  attr_type_        = AttrType::DATES;
+  value_.int_value_ = val;
+  length_           = sizeof(val);
+}
 void Value::set_boolean(bool val)
 {
   reset();
@@ -194,6 +205,9 @@ void Value::set_empty_string(int len)
 void Value::set_value(const Value &value)
 {
   switch (value.attr_type_) {
+    case AttrType::DATES: {
+      set_date(value.get_int());
+    } break;
     case AttrType::INTS: {
       set_int(value.get_int());
     } break;
@@ -250,6 +264,9 @@ int Value::compare(const Value &other) const { return DataType::type_instance(th
 int Value::get_int() const
 {
   switch (attr_type_) {
+    case AttrType::DATES: {
+      return value_.int_value_;
+    }
     case AttrType::CHARS: {
       try {
         return (int)(stol(value_.pointer_value_));

src/observer/common/value.h

@@ -116,6 +116,7 @@ class Value final
 public:
   void set_int(int val);
   void set_float(float val);
+  void set_date(int val);
   void set_string(const char *s, int len = 0);
   void set_empty_string(int len);
   void set_string_from_other(const Value &other);

src/observer/sql/executor/command_executor.cpp

@@ -19,6 +19,7 @@ See the Mulan PSL v2 for more details. */
 #include "sql/executor/create_index_executor.h"
 #include "sql/executor/create_table_executor.h"
 #include "sql/executor/desc_table_executor.h"
+#include "sql/executor/drop_table_executor.h"
 #include "sql/executor/help_executor.h"
 #include "sql/executor/load_data_executor.h"
 #include "sql/executor/set_variable_executor.h"
@@ -43,6 +44,11 @@ RC CommandExecutor::execute(SQLStageEvent *sql_event)
       rc = executor.execute(sql_event);
     } break;
 
+    case StmtType::DROP_TABLE: {
+      DropTableExecutor executor;
+      rc = executor.execute(sql_event);
+    } break;
+
     case StmtType::DESC_TABLE: {
       DescTableExecutor executor;
       rc = executor.execute(sql_event);

src/observer/sql/executor/drop_table_executor.cpp

@@ -0,0 +1,30 @@
+/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
+miniob is licensed under Mulan PSL v2.
+You can use this software according to the terms and conditions of the Mulan PSL v2.
+You may obtain a copy of Mulan PSL v2 at:
+         http://license.coscl.org.cn/MulanPSL2
+THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+See the Mulan PSL v2 for more details. */
+
+#include "sql/executor/drop_table_executor.h"
+
+#include "common/log/log.h"
+#include "event/session_event.h"
+#include "event/sql_event.h"
+#include "session/session.h"
+#include "sql/stmt/drop_table_stmt.h"
+#include "storage/db/db.h"
+
+RC DropTableExecutor::execute(SQLStageEvent *sql_event)
+{
+  Stmt    *stmt    = sql_event->stmt();
+  Session *session = sql_event->session_event()->session();
+  ASSERT(stmt->type() == StmtType::DROP_TABLE,
+      "drop table executor can not run this command: %d",
+      static_cast<int>(stmt->type()));
+
+  DropTableStmt *drop_table_stmt = static_cast<DropTableStmt *>(stmt);
+  return session->get_current_db()->drop_table(drop_table_stmt->table_name().c_str());
+}

src/observer/sql/executor/drop_table_executor.h

@@ -0,0 +1,24 @@
+/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
+miniob is licensed under Mulan PSL v2.
+You can use this software according to the terms and conditions of the Mulan PSL v2.
+You may obtain a copy of Mulan PSL v2 at:
+         http://license.coscl.org.cn/MulanPSL2
+THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+See the Mulan PSL v2 for more details. */
+
+#pragma once
+
+#include "common/sys/rc.h"
+
+class SQLStageEvent;
+
+class DropTableExecutor
+{
+public:
+  DropTableExecutor()          = default;
+  virtual ~DropTableExecutor() = default;
+
+  RC execute(SQLStageEvent *sql_event);
+};