diff --git a/deps/oblib/src/lib/ob_name_def.h b/deps/oblib/src/lib/ob_name_def.h
index 1b9970443..5fed7ef65 100644
--- a/deps/oblib/src/lib/ob_name_def.h
+++ b/deps/oblib/src/lib/ob_name_def.h
@@ -117,6 +117,7 @@
 #define N_NUM "num"
 #define N_SINH "sinh"
 #define N_COSH "cosh"
+#define N_DEGREES "degrees"
 #define N_TANH "tanh"
 #define N_RADIANS "radians"
 #define N_IS_JOIN "is_join"
diff --git a/src/share/object/ob_obj_cast.cpp b/src/share/object/ob_obj_cast.cpp
index 9947f872e..3d62652d6 100644
--- a/src/share/object/ob_obj_cast.cpp
+++ b/src/share/object/ob_obj_cast.cpp
@@ -2013,6 +2013,29 @@ static int double_time(
   return ret;
 }
 
+static int double_year(const ObObjType expect_type, ObObjCastParams &params,
+                       const ObObj &in, ObObj &out, const ObCastMode cast_mode)
+{
+  int ret = OB_SUCCESS;
+  if (OB_UNLIKELY(ObDoubleTC != in.get_type_class()
+                  || ObYearTC != ob_obj_type_class(expect_type))) {
+    ret = OB_ERR_UNEXPECTED;
+    LOG_ERROR("invalid input type",
+        K(ret), K(in), K(expect_type));
+  } else {
+    uint8_t value = 0;
+    double in_val = in.get_double();
+    in_val = in_val < 0 ? INT_MIN : in_val + 0.5;
+    uint64_t intvalue = static_cast<uint64_t>(in_val);
+    if (CAST_FAIL(ObTimeConverter::int_to_year(intvalue, value))) {
+    } else {
+      SET_RES_YEAR(out);
+    }
+  }
+  SET_RES_ACCURACY(DEFAULT_PRECISION_FOR_TEMPORAL, DEFAULT_SCALE_FOR_YEAR, DEFAULT_LENGTH_FOR_TEMPORAL);
+  return ret;
+}
+
 static int double_string(
     const ObObjType expect_type, ObObjCastParams& params, const ObObj& in, ObObj& out, const ObCastMode cast_mode)
 {
@@ -2382,6 +2405,10 @@ static int number_year(
     if (OB_ISNULL(value)) {
       ret = OB_ERR_UNEXPECTED;
       LOG_WARN("null pointer", K(ret), K(value));
+    } else if (in.get_number().is_negative()) {
+      uint8_t value = 0;
+      if (CAST_FAIL(ObTimeConverter::int_to_year(INT_MIN, value))) {
+      }
     } else {
       ObObj from;
       from.set_varchar(value, static_cast<ObString::obstr_size_t>(strlen(value)));
@@ -5772,7 +5799,7 @@ ObObjCastFunc OB_OBJ_CAST[ObMaxTC][ObMaxTC] = {
         double_datetime,         /*datetime*/
         double_date,             /*date*/
         double_time,             /*time*/
-        cast_not_support,        /*year*/
+        double_year,             /*year*/
         double_string,           /*string*/
         cast_not_support,        /*extend*/
         cast_not_support,        /*unknown*/
diff --git a/src/sql/CMakeLists.txt b/src/sql/CMakeLists.txt
index 0749eee12..634c3903a 100644
--- a/src/sql/CMakeLists.txt
+++ b/src/sql/CMakeLists.txt
@@ -354,6 +354,8 @@ ob_set_subtarget(ob_sql engine
   engine/expr/ob_expr_pi.cpp
   engine/expr/ob_expr_pi.h
   engine/expr/ob_expr_radians.cpp
+  engine/expr/ob_expr_degrees.cpp
+  engine/expr/ob_expr_degrees.h
   engine/expr/ob_expr_res_type_map.cpp
   engine/expr/ob_expr_result_type_util.cpp
   engine/expr/ob_expr_reverse.cpp
diff --git a/src/sql/engine/expr/ob_datum_cast.cpp b/src/sql/engine/expr/ob_datum_cast.cpp
index b1932a45e..9d6e04eaa 100644
--- a/src/sql/engine/expr/ob_datum_cast.cpp
+++ b/src/sql/engine/expr/ob_datum_cast.cpp
@@ -2230,7 +2230,14 @@ CAST_FUNC_NAME(number, year)
     if (OB_ISNULL(nmb_buf)) {
       ret = OB_ERR_UNEXPECTED;
       LOG_WARN("null pointer", K(ret), K(nmb_buf));
-    } else if (OB_FAIL(common_string_year(expr, ObString(strlen(nmb_buf), nmb_buf), res_datum))) {
+    } else if (nmb.is_negative()) {
+      // the year shouldn't accept a negative number, if we use the common_string_year.
+      // number like -0.4 could be converted to year, which should raise error in mysql
+      if (OB_FAIL(common_int_year(expr, INT_MIN, res_datum))) {
+        LOG_WARN("common_int_year failed", K(ret));
+      }
+    } else if (OB_FAIL(common_string_year(expr, ObString(strlen(nmb_buf), nmb_buf),
+                                          res_datum))) {
       LOG_WARN("common_string_year failed", K(ret));
     }
   }
@@ -2635,6 +2642,24 @@ CAST_FUNC_NAME(double, time)
   return ret;
 }
 
+CAST_FUNC_NAME(double, year)
+{
+  EVAL_ARG()
+  {
+    // When we insert 999999999999999999999.9(larger than max int) into a year field in mysql
+    // Mysql raise the same error as we insert 100 into a year field (1264).
+    // So the cast from double to int won't raise extra error. That's why we directly use
+    // static_cast here. Mysql will convert the double to nearest int and insert it to the year field.
+    double in_val = child_res->get_double();
+    in_val = in_val < 0 ? INT_MIN : in_val + 0.5;
+    int64_t val_int = static_cast<int64_t>(in_val);
+    if (OB_FAIL(common_int_year(expr, val_int, res_datum))) {
+      LOG_WARN("common_int_time failed", K(ret), K(val_int));
+    }
+  }
+  return ret;
+}
+
 CAST_FUNC_NAME(double, string)
 {
   EVAL_ARG()
@@ -5916,7 +5941,7 @@ ObExpr::EvalFunc OB_DATUM_CAST_ORACLE_IMPLICIT[ObMaxTC][ObMaxTC] = {
         cast_inconsistent_types, /*datetime*/
         cast_not_expected,       /*date*/
         cast_not_expected,       /*time*/
-        cast_not_expected,       /*year*/
+        double_year,             /*year*/
         double_string,           /*string*/
         cast_not_expected,       /*extend*/
         cast_not_expected,       /*unknown*/
diff --git a/src/sql/engine/expr/ob_expr_degrees.cpp b/src/sql/engine/expr/ob_expr_degrees.cpp
new file mode 100644
index 000000000..8e308845e
--- /dev/null
+++ b/src/sql/engine/expr/ob_expr_degrees.cpp
@@ -0,0 +1,86 @@
+// Copyright (c) 2014-2021 Alibaba Inc. All Right Reserved.
+// Author:
+//  liuqifan.lqf@antgroup.com
+#define USING_LOG_PREFIX SQL_ENG
+#include "sql/engine/expr/ob_expr_degrees.h"
+#include "lib/number/ob_number_v2.h"
+#include "sql/engine/expr/ob_expr_util.h"
+#include "sql/parser/ob_item_type.h"
+#include "sql/session/ob_sql_session_info.h"
+#include <cmath>
+
+using namespace oceanbase::common;
+using namespace oceanbase::sql;
+namespace oceanbase {
+namespace sql {
+
+const double ObExprDegrees::degrees_ratio_ = 180.0 / std::acos(-1);
+
+ObExprDegrees::ObExprDegrees(ObIAllocator &alloc)
+    : ObFuncExprOperator(alloc, T_FUN_SYS_DEGREES, N_DEGREES, 1, NOT_ROW_DIMENSION)
+{}
+
+ObExprDegrees::~ObExprDegrees()
+{}
+
+int ObExprDegrees::calc_result_type1(ObExprResType &type, ObExprResType &radian, ObExprTypeCtx &type_ctx) const
+{
+  UNUSED(type_ctx);
+  int ret = OB_SUCCESS;
+  if (NOT_ROW_DIMENSION != row_dimension_ || ObMaxType == radian.get_type()) {
+    ret = OB_ERR_INVALID_TYPE_FOR_OP;
+  } else {
+    type.set_double();
+    radian.set_calc_type(ObDoubleType);
+    ObExprOperator::calc_result_flag1(type, radian);
+  }
+  return ret;
+}
+
+int ObExprDegrees::calc_result1(ObObj &result, const ObObj &radian_obj, ObExprCtx &expr_ctx) const
+{
+  int ret = OB_SUCCESS;
+  double val = 0.0;
+  if (OB_ISNULL(expr_ctx.calc_buf_)) {
+    ret = OB_NOT_INIT;
+    LOG_WARN("expr_ctx.calc_buf_ is NULL", K(ret));
+  } else if (OB_FAIL(radian_obj.get_double(val))) {
+    LOG_WARN("get double from obj failed in degrees", K(ret), K(radian_obj), K(val));
+  } else {
+    result.set_double(val * degrees_ratio_);
+  }
+  return ret;
+}
+
+int ObExprDegrees::calc_degrees_expr(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &res_datum)
+{
+  int ret = OB_SUCCESS;
+  ObDatum *radian = NULL;
+  if (OB_FAIL(expr.args_[0]->eval(ctx, radian))) {
+    LOG_WARN("eval radian arg failed", K(ret), K(expr));
+  } else if (radian->is_null()) {
+    res_datum.set_null();
+  } else {
+    const double val = radian->get_double();
+    // cal result;
+    res_datum.set_double(val * degrees_ratio_);
+  }
+  return ret;
+}
+
+int ObExprDegrees::cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr, ObExpr &rt_expr) const
+{
+  int ret = OB_SUCCESS;
+  UNUSED(expr_cg_ctx);
+  UNUSED(raw_expr);
+  if (OB_UNLIKELY(1 != rt_expr.arg_cnt_) || (ObDoubleType != rt_expr.args_[0]->datum_meta_.type_)) {
+    ret = OB_ERR_UNEXPECTED;
+    LOG_WARN("invalid arg_cnt_ or res type is invalid", K(ret), K(rt_expr));
+  } else {
+    rt_expr.eval_func_ = calc_degrees_expr;
+  }
+  return ret;
+}
+
+}  // namespace sql
+}  // namespace oceanbase
diff --git a/src/sql/engine/expr/ob_expr_degrees.h b/src/sql/engine/expr/ob_expr_degrees.h
new file mode 100644
index 000000000..83cbd09cd
--- /dev/null
+++ b/src/sql/engine/expr/ob_expr_degrees.h
@@ -0,0 +1,30 @@
+//
+// Author:
+//  liuqifan.lqf@antgroup.com
+//
+
+#ifndef OCEANBASE_SQL_ENGINE_EXPR_DEGREES_
+#define OCEANBASE_SQL_ENGINE_EXPR_DEGREES_
+
+#include "sql/engine/expr/ob_expr_operator.h"
+
+namespace oceanbase {
+namespace sql {
+
+class ObExprDegrees : public ObFuncExprOperator {
+public:
+  explicit ObExprDegrees(common::ObIAllocator &alloc);
+  virtual ~ObExprDegrees();
+  virtual int calc_result_type1(ObExprResType &type, ObExprResType &radian, common::ObExprTypeCtx &type_ctx) const;
+  virtual int calc_result1(common::ObObj &result, const common::ObObj &radian_obj, common::ObExprCtx &expr_ctx) const;
+  static int calc_degrees_expr(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &res_datum);
+  virtual int cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr, ObExpr &rt_expr) const override;
+
+private:
+  const static double degrees_ratio_;
+  DISALLOW_COPY_AND_ASSIGN(ObExprDegrees);
+};
+
+}  // namespace sql
+}  // namespace oceanbase
+#endif
diff --git a/src/sql/engine/expr/ob_expr_eval_functions.cpp b/src/sql/engine/expr/ob_expr_eval_functions.cpp
index 17f9c45d0..befda14fe 100644
--- a/src/sql/engine/expr/ob_expr_eval_functions.cpp
+++ b/src/sql/engine/expr/ob_expr_eval_functions.cpp
@@ -184,6 +184,7 @@
 #include "ob_expr_to_single_byte.h"
 #include "ob_expr_to_multi_byte.h"
 #include "ob_expr_convert_tz.h"
+#include "ob_expr_degrees.h"
 
 namespace oceanbase {
 using namespace common;
@@ -671,7 +672,7 @@ static ObExpr::EvalFunc g_expr_eval_functions[] = {
     NULL,                                     /* 411 */
     NULL,                                     /* 412 */
     NULL,                                     /* 413 */
-    NULL,                                     /* 414 */
+    ObExprDegrees::calc_degrees_expr,         /* 414 */
     NULL,                                     /* 415 */
     NULL,                                     /* 416 */
     NULL,                                     /* 417 */
@@ -717,7 +718,7 @@ static ObExpr::EvalFunc g_expr_eval_functions[] = {
     ObExprInet6Ntoa::calc_inet6_ntoa,         /* 457 */
     NULL,                                     // ObExprWeightString::eval_weight_string,  /* 458 */
     ObExprConvertTZ::eval_convert_tz,         /* 459 */
-    ObExprCrc32::calc_crc32_expr,             /* 460 */
+    ObExprCrc32::calc_crc32_expr              /* 460 */
 };
 
 REG_SER_FUNC_ARRAY(OB_SFA_SQL_EXPR_EVAL, g_expr_eval_functions, ARRAYSIZEOF(g_expr_eval_functions));
diff --git a/src/sql/engine/expr/ob_expr_operator_factory.cpp b/src/sql/engine/expr/ob_expr_operator_factory.cpp
index 0835ea631..3b84eaf7b 100644
--- a/src/sql/engine/expr/ob_expr_operator_factory.cpp
+++ b/src/sql/engine/expr/ob_expr_operator_factory.cpp
@@ -268,6 +268,7 @@
 #include "sql/engine/expr/ob_expr_quarter.h"
 #include "sql/engine/expr/ob_expr_bit_length.h"
 #include "sql/engine/expr/ob_expr_convert_tz.h"
+#include "sql/engine/expr/ob_expr_degrees.h"
 
 using namespace oceanbase::common;
 namespace oceanbase {
@@ -677,6 +678,7 @@ void ObExprOperatorFactory::register_expr_operators()
   REG_OP(ObExprLastDay);
   REG_OP(ObExprTimeFormat);
   REG_OP(ObExprTimestamp);
+  REG_OP(ObExprDegrees);
   // register oracle system function
   REG_OP_ORCL(ObExprSysConnectByPath);
   REG_OP_ORCL(ObExprTimestampNvl);
diff --git a/src/sql/parser/ob_item_type.h b/src/sql/parser/ob_item_type.h
index a31ae2639..faab53b5a 100644
--- a/src/sql/parser/ob_item_type.h
+++ b/src/sql/parser/ob_item_type.h
@@ -426,6 +426,7 @@ typedef enum ObItemType {
   T_FUN_SYS_QUARTER = 711,
   T_FUN_SYS_BIT_LENGTH = 712,
   T_FUN_SYS_PI = 713,
+  T_FUN_SYS_DEGREES = 715,
   T_FUN_SYS_EXPORT_SET = 721,
   
   T_FUN_SYS_INET6NTOA = 722,