Files
oceanbase/src/sql/optimizer/ob_log_count.cpp
2024-02-09 19:58:19 +00:00

215 lines
7.9 KiB
C++

/**
* 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_OPT
#include "sql/optimizer/ob_log_count.h"
#include "sql/optimizer/ob_optimizer_util.h"
#include "sql/optimizer/ob_opt_est_cost.h"
#include "sql/optimizer/ob_log_plan.h"
#include "sql/rewrite/ob_transform_utils.h"
#include "sql/optimizer/ob_opt_selectivity.h"
#include "sql/optimizer/ob_join_order.h"
#include "common/ob_smart_call.h"
using namespace oceanbase::sql;
using namespace oceanbase::common;
using namespace oceanbase::sql::log_op_def;
namespace oceanbase
{
namespace sql
{
int ObLogCount::est_cost()
{
int ret = OB_SUCCESS;
double sel = 1.0;
ObLogicalOperator *child = NULL;
if (OB_ISNULL(get_plan()) || OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(get_plan()), K(child), K(ret));
} else if (OB_FALSE_IT(get_plan()->get_selectivity_ctx().init_op_ctx(
&child->get_output_equal_sets(), child->get_card()))) {
} else if (OB_FAIL(ObOptSelectivity::calculate_selectivity(get_plan()->get_update_table_metas(),
get_plan()->get_selectivity_ctx(),
get_filter_exprs(),
sel,
get_plan()->get_predicate_selectivities()))) {
LOG_WARN("failed to calculate selectivity", K(ret));
} else {
double child_card = child->get_card();
double child_cost = child->get_cost();
if (OB_FAIL(inner_est_cost(child_card, child_cost, true, sel, op_cost_))) {
LOG_WARN("failed to est count cost", K(ret));
} else {
set_cost(op_cost_ + child_cost);
set_card(child_card * sel);
}
}
return ret;
}
int ObLogCount::est_width()
{
int ret = OB_SUCCESS;
double width = 0.0;
ObLogicalOperator *child = NULL;
if (OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(child), K(ret));
} else {
width = child->get_width() + 4;
set_width(width);
}
return ret;
}
int ObLogCount::do_re_est_cost(EstimateCostInfo &param, double &card, double &op_cost, double &cost)
{
int ret = OB_SUCCESS;
double sel = 1.0;
ObLogicalOperator *child = NULL;
if (OB_ISNULL(get_plan()) ||
OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(get_plan()), K(child), K(ret));
} else if (OB_FALSE_IT(get_plan()->get_selectivity_ctx().init_op_ctx(
&child->get_output_equal_sets(), child->get_card()))) {
} else if (OB_FAIL(ObOptSelectivity::calculate_selectivity(get_plan()->get_basic_table_metas(),
get_plan()->get_selectivity_ctx(),
get_filter_exprs(),
sel,
get_plan()->get_predicate_selectivities()))) {
LOG_WARN("failed to calc selectivity", K(ret));
} else {
double child_card = child->get_card();
double child_cost = child->get_cost();
if (param.need_row_count_ >= 0 && param.need_row_count_ < get_card()) {
//child need row count
if (sel > OB_DOUBLE_EPSINON) {
param.need_row_count_ /= sel;
}
}
if (OB_FAIL(SMART_CALL(child->re_est_cost(param, child_card, child_cost)))) {
LOG_WARN("failed to est child cost", K(ret));
} else if (OB_FAIL(inner_est_cost(child_card, child_cost, false, sel, op_cost))) {
LOG_WARN("failed to est count cost", K(ret));
} else {
cost = op_cost + child_cost;
card = child_card * sel;
}
}
return ret;
}
int ObLogCount::inner_est_cost(double &child_card,
double &child_cost,
bool need_re_est_child_cost,
double sel,
double &op_cost)
{
int ret = OB_SUCCESS;
ObLogicalOperator *child = NULL;
int64_t limit_count = 0.0;
bool is_null_value = false;
if (OB_ISNULL(get_plan()) ||
OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(get_plan()), K(child), K(ret));
} else {
ObOptimizerContext &opt_ctx = get_plan()->get_optimizer_context();
if (NULL != rownum_limit_expr_ &&
!rownum_limit_expr_->has_flag(CNT_DYNAMIC_PARAM)) {
if (OB_FAIL(ObTransformUtils::get_limit_value(rownum_limit_expr_,
opt_ctx.get_params(),
opt_ctx.get_exec_ctx(),
&opt_ctx.get_allocator(),
limit_count,
is_null_value))) {
LOG_WARN("Get limit count num error", K(ret));
} else if (limit_count > child_card) {
//do nothing
} else if (sel > 0 && need_re_est_child_cost) {
EstimateCostInfo param;
param.need_row_count_ = limit_count / sel;
param.override_ = false;
if (OB_FAIL(child->re_est_cost(param, child_card, child_cost))) {
LOG_WARN("failed to est child cost", K(ret));
}
}
}
op_cost = ObOptEstCost::cost_filter_rows(child_card, get_filter_exprs(),
opt_ctx);
}
return ret;
}
int ObLogCount::get_op_exprs(ObIArray<ObRawExpr*> &all_exprs)
{
int ret = OB_SUCCESS;
if (NULL != rownum_expr_ && OB_FAIL(all_exprs.push_back(rownum_expr_))) {
LOG_WARN("failed to add exprs", K(ret));
} else if (NULL != rownum_limit_expr_ && OB_FAIL(all_exprs.push_back(rownum_limit_expr_))) {
LOG_WARN("failed to add exprs", K(ret));
} else if (OB_FAIL(ObLogicalOperator::get_op_exprs(all_exprs))) {
LOG_WARN("failed to get op exprs", K(ret));
} else { /*do nothing*/ }
return ret;
}
int ObLogCount::get_plan_item_info(PlanText &plan_text,
ObSqlPlanItem &plan_item)
{
int ret = OB_SUCCESS;
if (OB_FAIL(ObLogicalOperator::get_plan_item_info(plan_text, plan_item))) {
LOG_WARN("failed to get base plan item info", K(ret));
} else if (NULL != rownum_limit_expr_) {
BEGIN_BUF_PRINT;
EXPLAIN_PRINT_EXPR(rownum_limit_expr_, type);
END_BUF_PRINT(plan_item.special_predicates_,
plan_item.special_predicates_len_);
}
return ret;
}
int ObLogCount::inner_replace_op_exprs(ObRawExprReplacer &replacer)
{
int ret = OB_SUCCESS;
if (NULL != rownum_limit_expr_ && OB_FAIL(replace_expr_action(replacer, rownum_limit_expr_))) {
LOG_WARN("failed to replace expr", K(ret));
}
return ret;
}
int ObLogCount::is_my_fixed_expr(const ObRawExpr *expr, bool &is_fixed)
{
int ret = OB_SUCCESS;
is_fixed = false;
ObRawExpr *rownum_expr = NULL;
if (OB_ISNULL(get_stmt())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(ret), K(get_stmt()));
} else if (OB_FAIL(get_stmt()->get_rownum_expr(rownum_expr))) {
LOG_WARN("failed to get rownum expr", K(ret));
} else if (OB_ISNULL(rownum_expr)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(ret));
} else if (expr == rownum_expr) {
is_fixed = true;
}
return ret;
}
} /* namespace sql */
} /* namespace oceanbase */