implement of any value expr in mysql mode

src/sql/engine/expr/ob_expr_any_value.cpp

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2014-2021 Alibaba Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * ob_expr_any_value.cpp is for any_value function
+ *
+ * Date: 2021/7/9
+ *
+ * Authors:
+ *     ailing.lcq<ailing.lcq@alibaba-inc.com>
+ *
+ */
+
+#include "sql/engine/expr/ob_expr_any_value.h"
+
+using namespace oceanbase::common;
+
+namespace oceanbase {
+namespace sql {
+
+ObExprAnyValue::ObExprAnyValue(ObIAllocator &alloc)
+    : ObFuncExprOperator(alloc, T_FUN_SYS_ANY_VALUE, N_ANY_VAL, 1, NOT_ROW_DIMENSION)
+{}
+
+ObExprAnyValue::~ObExprAnyValue()
+{}
+
+int ObExprAnyValue::calc_result_type1(ObExprResType &type, ObExprResType &arg, common::ObExprTypeCtx &) const
+{
+  int ret = OB_SUCCESS;
+  type = arg;
+  return ret;
+}
+
+int ObExprAnyValue::calc_result1(common::ObObj &result, const common::ObObj &arg, common::ObExprCtx &expr_ctx) const
+{
+  UNUSED(expr_ctx);
+  int ret = OB_SUCCESS;
+  result = arg;
+  return ret;
+}
+
+int ObExprAnyValue::cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr, ObExpr &rt_expr) const
+{
+  UNUSED(raw_expr);
+  UNUSED(expr_cg_ctx);
+  rt_expr.eval_func_ = ObExprAnyValue::eval_any_value;
+  return OB_SUCCESS;
+}
+
+int ObExprAnyValue::eval_any_value(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_datum)
+{
+  int ret = OB_SUCCESS;
+  ObDatum *arg = NULL;
+  if (OB_FAIL(expr.eval_param_value(ctx, arg))) {
+    SERVER_LOG(WARN, "expr evaluate parameter failed", K(ret));
+  } else {
+    expr_datum.set_datum(*arg);
+  }
+  return ret;
+}
+
+}  // namespace sql
+}  // namespace oceanbase

src/sql/engine/expr/ob_expr_any_value.h

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2014-2021 Alibaba Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * ob_expr_any_value.h is for any_value function
+ *
+ * Date: 2021/7/9
+ *
+ * Authors:
+ *     ailing.lcq<ailing.lcq@alibaba-inc.com>
+ *
+ */
+#ifndef _OB_EXPR_ANY_VALUE_H_
+#define _OB_EXPR_ANY_VALUE_H_
+
+#include "sql/engine/expr/ob_expr_operator.h"
+
+namespace oceanbase {
+namespace sql {
+class ObExprAnyValue : public ObFuncExprOperator {
+public:
+  explicit ObExprAnyValue(common::ObIAllocator &alloc);
+  virtual ~ObExprAnyValue();
+
+  virtual int calc_result_type1(
+      ObExprResType &type, ObExprResType &arg, common::ObExprTypeCtx &type_ctx) const override;
+
+  virtual int calc_result1(common::ObObj &result, const common::ObObj &arg, common::ObExprCtx &expr_ctx) const override;
+
+  virtual int cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr, ObExpr &rt_expr) const override;
+
+  static int eval_any_value(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_datum);
+
+private:
+  DISALLOW_COPY_AND_ASSIGN(ObExprAnyValue) const;
+};
+}  // namespace sql
+}  // namespace oceanbase
+#endif /* _OB_EXPR_ANY_VALUE_H_ */
+
+// select any_value();

src/sql/engine/expr/ob_expr_eval_functions.cpp

@@ -186,6 +186,7 @@
 #include "ob_expr_convert_tz.h"
 #include "ob_expr_degrees.h"
 #include "ob_expr_weight_string.h"
+#include "ob_expr_any_value.h"
 
 namespace oceanbase {
 using namespace common;
@@ -671,7 +672,7 @@ static ObExpr::EvalFunc g_expr_eval_functions[] = {
     ObExprPeriodAdd::calc_periodadd,          /* 409 */
     NULL,                                     /* 410 */
     NULL,                                     /* 411 */
-    NULL,                                     /* 412 */
+    ObExprAnyValue::eval_any_value,           /* 412 */
     NULL,                                     /* 413 */
     ObExprDegrees::calc_degrees_expr,         /* 414 */
     NULL,                                     /* 415 */

src/sql/engine/expr/ob_expr_operator_factory.cpp

@@ -270,6 +270,7 @@
 #include "sql/engine/expr/ob_expr_convert_tz.h"
 #include "sql/engine/expr/ob_expr_degrees.h"
 #include "sql/engine/expr/ob_expr_weight_string.h"
+#include "sql/engine/expr/ob_expr_any_value.h"
 
 using namespace oceanbase::common;
 namespace oceanbase {
@@ -610,6 +611,7 @@ void ObExprOperatorFactory::register_expr_operators()
   REG_OP(ObExprTruncate);
   REG_OP(ObExprDllUdf);
   REG_OP(ObExprExp);
+  REG_OP(ObExprAnyValue);
   /* subquery comparison experator */
   REG_OP(ObExprSubQueryRef);
   REG_OP(ObExprSubQueryEqual);