[FEAT MERGE] [v4.2] add table generator and several random utility functions

2023-04-13 08:22:22 +00:00
parent 94159e6675
commit 27488211d2
34 changed files with 1659 additions and 79 deletions
--- a/src/sql/engine/expr/ob_expr_randstr.cpp
+++ b/src/sql/engine/expr/ob_expr_randstr.cpp
@ -0,0 +1,126 @@
+/**
+ * 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.
+ */
+
+#define USING_LOG_PREFIX  SQL_ENG
+#include "sql/engine/expr/ob_expr_randstr.h"
+#include "sql/engine/ob_exec_context.h"
+
+namespace oceanbase
+{
+using namespace common;
+namespace sql
+{
+
+ObExprRandstr::ObExprRandstr(common::ObIAllocator &alloc)
+	: ObFuncExprOperator(alloc, T_FUN_SYS_RANDSTR, "randstr", 2, NOT_ROW_DIMENSION)
+{
+}
+
+ObExprRandstr::~ObExprRandstr()
+{
+}
+
+int ObExprRandstr::calc_result_type2(ObExprResType &type,
+                                     ObExprResType &len,
+                                     ObExprResType &seed,
+                                     common::ObExprTypeCtx &type_ctx) const
+{
+	UNUSED(type_ctx);
+	int ret = OB_SUCCESS;
+	len.set_calc_type(ObIntType);
+  seed.set_calc_type(ObIntType);
+  if (lib::is_mysql_mode()) {
+    int64_t mbmaxlen = 0;
+    if (OB_FAIL(ObCharset::get_mbmaxlen_by_coll(
+                common::ObCharset::get_default_collation(common::ObCharset::get_default_charset()), mbmaxlen))) {
+      ret = OB_ERR_UNEXPECTED;
+      SQL_RESV_LOG(WARN, "fail to get mbmaxlen");
+    } else if (0 == mbmaxlen){
+      ret = OB_ERR_UNEXPECTED;
+      LOG_WARN("mb maxlen invalid");
+    } else {
+      type.set_type(ObVarcharType);
+      // must divide by mbmaxlen,
+      // otherwise create table as select would fail with randstr() function
+      type.set_length(OB_MAX_VARCHAR_LENGTH / mbmaxlen);
+    }
+  } else {
+    type.set_collation_type(type_ctx.get_coll_type());
+    type.set_collation_level(CS_LEVEL_IMPLICIT);
+    type.set_length_semantics(LS_CHAR);
+    type.set_type(ObVarcharType);
+    type.set_length(OB_MAX_ORACLE_VARCHAR_LENGTH);
+  }
+  type.set_collation_level(common::CS_LEVEL_IMPLICIT);
+  type.set_collation_type(common::ObCharset::get_default_collation(common::ObCharset::get_default_charset()));
+	return ret;
+}
+
+int ObExprRandstr::calc_random_str(const ObExpr &expr,
+                                   ObEvalCtx &ctx,
+                                   ObDatum &res_datum)
+{
+  int ret = OB_SUCCESS;
+  int64_t max_size = 0;
+  if (OB_UNLIKELY(2 != expr.arg_cnt_)) {
+    ret = OB_ERR_UNEXPECTED;
+    LOG_WARN("unexpected arg_cnt", K(ret), K(expr.arg_cnt_));
+  } else if (OB_FAIL(expr.eval_param_value(ctx))) {
+    LOG_WARN("expr.eval_param_value failed", K(ret));
+  } else if (OB_FAIL(ctx.exec_ctx_.get_my_session()->get_max_allowed_packet(max_size))) {
+    LOG_WARN("get max length failed", K(ret));
+  } else {
+    int64_t rand_res = 0;
+    ObDatum &len = expr.locate_param_datum(ctx, 0);
+    ObDatum &seed = expr.locate_param_datum(ctx, 1);
+    if (len.is_null() || seed.is_null()) {
+      res_datum.set_null();
+    } else if (OB_UNLIKELY(len.get_int() < 0)) {
+      res_datum.set_null();
+    } else if (OB_UNLIKELY(len.get_int() > max_size)) {
+      res_datum.set_null();
+      LOG_USER_WARN(OB_ERR_FUNC_RESULT_TOO_LARGE, "randstr", static_cast<int>(max_size));
+    } else {
+      ObString output;
+      ObExprStrResAlloc expr_res_alloc(expr, ctx);
+      int64_t len_val = len.get_int();
+      int64_t seed_val = seed.get_int();
+      char *buf = static_cast<char *>(expr_res_alloc.alloc(len_val));
+      if (OB_ISNULL(buf)) {
+        ret = OB_ALLOCATE_MEMORY_FAILED;
+        LOG_WARN("fail alloc memory", K(ret), K(len_val));
+      } else {
+        static const char dict[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+        for (int64_t i = 0; i < len_val && OB_SUCC(ret); ++i) {
+          // LCG, Linear Congruential Method for Generating Pseudo Random Number
+          seed_val = (seed_val * 1103515245 + 12345) & ((1U << 31) - 1);
+          buf[i] = dict[seed_val % (sizeof(dict) - 1)];
+        }
+        output.assign_ptr(buf, static_cast<int32_t>(len_val));
+        res_datum.set_string(output);
+      }
+    }
+  }
+  return ret;
+}
+
+int ObExprRandstr::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);
+  rt_expr.eval_func_ = ObExprRandstr::calc_random_str;
+  return ret;
+}
+} /* namespace sql */
+} /* namespace oceanbase */