[FEAT MERGE] OB Support XMLType

Co-authored-by: simonjoylet <simonjoylet@gmail.com>

src/sql/engine/expr/ob_expr_xmlparse.h

@@ -0,0 +1,70 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * 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 PubL v2 for more details.
+ * This file is for func xmlparse.
+ */
+
+#ifndef OCEANBASE_SRC_SQL_ENGINE_EXPR_OB_EXPR_XMLPARSE_H
+#define OCEANBASE_SRC_SQL_ENGINE_EXPR_OB_EXPR_XMLPARSE_H
+
+#include "sql/engine/expr/ob_expr_operator.h"
+#include "sql/engine/expr/ob_expr_lob_utils.h"
+
+namespace oceanbase
+{
+
+namespace sql
+{
+
+class ObExprXmlparse : public ObFuncExprOperator
+{
+  public:
+  explicit ObExprXmlparse(common::ObIAllocator &alloc);
+  virtual ~ObExprXmlparse();
+  virtual int calc_result_typeN(ObExprResType& type,
+                                ObExprResType* types_stack,
+                                int64_t param_num,
+                                common::ObExprTypeCtx& type_ctx)
+                                const override;
+  static int eval_xmlparse(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &res) { return OB_NOT_SUPPORTED; }
+  virtual int cg_expr(ObExprCGCtx &expr_cg_ctx,
+                      const ObRawExpr &raw_expr,
+                      ObExpr &rt_expr)
+                      const override;
+
+private:
+
+  /* process xml_doc_type */
+  const static uint8_t OB_XML_DOC_TYPE_COUNT = 3;
+  const static uint8_t OB_XML_DOCUMENT = 0;
+  const static uint8_t OB_XML_CONTENT = 1;
+  const static uint8_t OB_XML_DOC_TYPE_IMPLICIT = 2;
+
+  /* process xml wellformed */
+  const static uint8_t OB_WELLFORMED_COUNT = 3;
+  const static uint8_t OB_XML_WELLFORMED = 0;
+  const static uint8_t OB_XML_NOT_WELLFORMED = 1;
+  const static uint8_t OB_WELLFORMED_IMPLICIT = 2;
+
+  static int get_clause_opt(const ObExpr &expr,
+                            ObEvalCtx &ctx,
+                            uint8_t index,
+                            uint8_t &type,
+                            uint8_t size_para);
+
+private:
+    DISALLOW_COPY_AND_ASSIGN(ObExprXmlparse);
+};
+
+} // sql
+} // oceanbase
+
+
+#endif // OCEANBASE_SRC_SQL_ENGINE_EXPR_OB_EXPR_XMLPARSE_H