Files
oceanbase/src/sql/optimizer/ob_log_distinct.cpp
2024-02-21 09:19:05 +00:00

388 lines
14 KiB
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/**
* 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_distinct.h"
#include "sql/optimizer/ob_log_exchange.h"
#include "sql/optimizer/ob_log_sort.h"
#include "sql/optimizer/ob_log_set.h"
#include "sql/optimizer/ob_log_operator_factory.h"
#include "sql/optimizer/ob_join_order.h"
#include "sql/optimizer/ob_log_operator_factory.h"
#include "ob_opt_est_cost.h"
#include "ob_select_log_plan.h"
#include "ob_optimizer_util.h"
#include "ob_opt_selectivity.h"
#include "common/ob_smart_call.h"
#include "sql/rewrite/ob_transform_utils.h"
using namespace oceanbase;
using namespace sql;
using namespace oceanbase::common;
namespace oceanbase
{
namespace sql
{
const char *ObLogDistinct::get_name() const
{
return MERGE_AGGREGATE == algo_ ? "MERGE DISTINCT" : "HASH DISTINCT";
}
int ObLogDistinct::get_plan_item_info(PlanText &plan_text,
ObSqlPlanItem &plan_item)
{
int ret = OB_SUCCESS;
const ObIArray<ObRawExpr*> &distinct = distinct_exprs_;
if (OB_FAIL(ObLogicalOperator::get_plan_item_info(plan_text, plan_item))) {
LOG_WARN("failed to get base plan item info", K(ret));
} else {
BEGIN_BUF_PRINT;
EXPLAIN_PRINT_EXPRS(distinct, type);
if (OB_SUCC(ret) && is_block_mode_) {
ret = BUF_PRINTF(", block");
}
END_BUF_PRINT(plan_item.special_predicates_,
plan_item.special_predicates_len_);
}
return ret;
}
int ObLogDistinct::inner_replace_op_exprs(ObRawExprReplacer &replacer)
{
int ret = OB_SUCCESS;
if(OB_FAIL(replace_exprs_action(replacer, distinct_exprs_))) {
SQL_OPT_LOG(WARN, "failed to replace agg exprs in distinct op", K(ret));
}
return ret;
}
int ObLogDistinct::compute_op_ordering()
{
int ret = OB_SUCCESS;
ObLogicalOperator *child = NULL;
if (algo_ == HASH_AGGREGATE) {
// do nothing
} else if (OB_FAIL(ObLogicalOperator::compute_op_ordering())) {
LOG_WARN("failed to compute op ordering", K(ret));
} else {
is_local_order_ = is_fully_partition_wise() && !get_op_ordering().empty();
}
return ret;
}
int ObLogDistinct::est_width()
{
int ret = OB_SUCCESS;
double width = 0.0;
ObSEArray<ObRawExpr*, 16> output_exprs;
if (OB_ISNULL(get_plan())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("invalid plan", K(ret));
} else if (OB_FAIL(get_distinct_output_exprs(output_exprs))) {
LOG_WARN("failed to get distinct output exprs", K(ret));
} else if (OB_FAIL(ObOptEstCost::estimate_width_for_exprs(get_plan()->get_basic_table_metas(),
get_plan()->get_selectivity_ctx(),
output_exprs,
width))) {
LOG_WARN("failed to estimate width for output distinct exprs", K(ret));
} else {
set_width(width);
LOG_TRACE("est width for distinct", K(output_exprs), K(width));
}
return ret;
}
int ObLogDistinct::get_distinct_output_exprs(ObIArray<ObRawExpr *> &output_exprs)
{
int ret = OB_SUCCESS;
ObLogPlan *plan = NULL;
ObSEArray<ObRawExpr*, 16> candi_exprs;
ObSEArray<ObRawExpr*, 16> extracted_col_aggr_winfunc_exprs;
if (OB_ISNULL(plan = get_plan())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("invalid input", K(ret));
} else if (OB_FAIL(append_array_no_dup(candi_exprs, plan->get_select_item_exprs_for_width_est()))) {
LOG_WARN("failed to add into output exprs", K(ret));
} else if (OB_FAIL(append_array_no_dup(candi_exprs, plan->get_orderby_exprs_for_width_est()))) {
LOG_WARN("failed to add into output exprs", K(ret));
} else if (OB_FAIL(ObRawExprUtils::extract_col_aggr_winfunc_exprs(candi_exprs,
extracted_col_aggr_winfunc_exprs))) {
} else if (OB_FAIL(append_array_no_dup(output_exprs, extracted_col_aggr_winfunc_exprs))) {
LOG_WARN("failed to add into output exprs", K(ret));
} else {/*do nothing*/}
return ret;
}
int ObLogDistinct::est_cost()
{
int ret = OB_SUCCESS;
double distinct_cost = 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 if (OB_UNLIKELY(total_ndv_ < 0)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected total ndv", K(total_ndv_), K(ret));
} else if (OB_FAIL(inner_est_cost(get_parallel(), child->get_card(), total_ndv_, distinct_cost))) {
LOG_WARN("failed to est distinct cost", K(ret));
} else {
set_op_cost(distinct_cost);
set_cost(child->get_cost() + distinct_cost);
set_card(total_ndv_);
}
return ret;
}
int ObLogDistinct::do_re_est_cost(EstimateCostInfo &param, double &card, double &op_cost, double &cost)
{
int ret = OB_SUCCESS;
ObLogicalOperator *child = NULL;
if (OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpect null child", K(ret));
} else if (OB_UNLIKELY(total_ndv_ < 0)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected total ndv", K(total_ndv_), K(ret));
} else {
double child_card = child->get_card();
double child_cost = child->get_cost();
double child_ndv = total_ndv_;
const int64_t parallel = param.need_parallel_;
double origin_child_card = child_card;
bool need_scale_ndv = false;
if (param.need_row_count_ >= 0 &&
child_card > 0 &&
total_ndv_ > 0 &&
param.need_row_count_ < child_card &&
param.need_row_count_ < total_ndv_) {
child_ndv = param.need_row_count_;
param.need_row_count_ = child_card * (1 - std::pow((1 - child_ndv / total_ndv_), total_ndv_ / child_card));
} else {
param.need_row_count_ = -1;
need_scale_ndv = true;
}
if (OB_FAIL(SMART_CALL(child->re_est_cost(param, child_card, child_cost)))) {
LOG_WARN("failed to re est child cost", K(ret));
} else if (need_scale_ndv &&
FALSE_IT(child_ndv = std::min(child_ndv, ObOptSelectivity::scale_distinct(child_card, origin_child_card, child_ndv)))) {
// do nothing
} else if (OB_FAIL(inner_est_cost(parallel, child_card, child_ndv, op_cost))) {
LOG_WARN("failed to est distinct cost", K(ret));
} else {
cost = child_cost + op_cost;
card = child_ndv;
if (param.override_) {
total_ndv_ = child_ndv;
}
}
}
return ret;
}
int ObLogDistinct::inner_est_cost(const int64_t parallel, double child_card, double child_ndv, double &op_cost)
{
int ret = OB_SUCCESS;
double per_dop_card = 0.0;
double per_dop_ndv = 0.0;
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(child), K(ret));
} else if (OB_UNLIKELY(parallel < 1)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected parallel", K(parallel), K(ret));
} else {
ObOptimizerContext &opt_ctx = get_plan()->get_optimizer_context();
per_dop_card = child_card / parallel;
if (parallel > 1) {
if (is_push_down()) {
per_dop_ndv = ObOptSelectivity::scale_distinct(per_dop_card, child_card, child_ndv);
} else {
per_dop_ndv = child_ndv / parallel;
}
} else {
per_dop_ndv = child_ndv;
}
if (MERGE_AGGREGATE == algo_) {
op_cost = ObOptEstCost::cost_merge_distinct(per_dop_card,
per_dop_ndv,
child->get_width(),
distinct_exprs_,
opt_ctx);
} else {
op_cost = ObOptEstCost::cost_hash_distinct(per_dop_card,
per_dop_ndv,
child->get_width(),
distinct_exprs_,
opt_ctx);
}
}
return ret;
}
uint64_t ObLogDistinct::hash(uint64_t seed) const
{
seed = do_hash(algo_, seed);
seed = ObLogicalOperator::hash(seed);
return seed;
}
int ObLogDistinct::compute_fd_item_set()
{
int ret = OB_SUCCESS;
const ObLogicalOperator *child = NULL;
ObFdItemSet *fd_item_set = NULL;
ObTableFdItem *fd_item = NULL;
if (OB_ISNULL(child = get_child(ObLogicalOperator::first_child)) ||
OB_ISNULL(my_plan_) || OB_ISNULL(get_stmt())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpect null", K(ret), K(child), K(my_plan_), K(get_stmt()));
} else if (OB_FAIL(my_plan_->get_fd_item_factory().create_fd_item_set(fd_item_set))) {
LOG_WARN("failed to create fd item set", K(ret));
} else if (OB_FAIL(fd_item_set->assign(child->get_fd_item_set()))) {
LOG_WARN("failed to assign fd item set", K(ret));
} else if (!ObTransformUtils::need_compute_fd_item_set(distinct_exprs_)) {
//do nothing
}else if (OB_FAIL(my_plan_->get_fd_item_factory().create_table_fd_item(fd_item,
true,
distinct_exprs_,
get_table_set()))) {
LOG_WARN("failed to create fd item", K(ret));
} else if (OB_FAIL(fd_item_set->push_back(fd_item))) {
LOG_WARN("failed to push back fd item", K(ret));
} else if (OB_FAIL(deduce_const_exprs_and_ft_item_set(*fd_item_set))) {
LOG_WARN("falied to deduce fd item set", K(ret));
} else {
set_fd_item_set(fd_item_set);
}
return ret;
}
int ObLogDistinct::allocate_granule_pre(AllocGIContext &ctx)
{
int ret = OB_SUCCESS;
if (OB_FAIL(pw_allocate_granule_pre(ctx))) {
LOG_WARN("failed to allocate partition wise granule", K(ret));
} else { /*do nothing*/ }
return ret;
}
int ObLogDistinct::allocate_granule_post(AllocGIContext &ctx)
{
return pw_allocate_granule_post(ctx);
}
int ObLogDistinct::get_op_exprs(ObIArray<ObRawExpr*> &all_exprs)
{
int ret = OB_SUCCESS;
if (OB_FAIL(append(all_exprs, distinct_exprs_))) {
LOG_WARN("failed to add exprs to ctx", 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 ObLogDistinct::print_outline_data(PlanText &plan_text)
{
int ret = OB_SUCCESS;
char *buf = plan_text.buf_;
int64_t &buf_len = plan_text.buf_len_;
int64_t &pos = plan_text.pos_;
const ObDMLStmt *stmt = NULL;
ObString qb_name;
const ObLogicalOperator *child = NULL;
const ObLogicalOperator *op = NULL;
if (is_push_down()) {
/* print outline in top distinct */
} else if (OB_ISNULL(get_plan()) || OB_ISNULL(stmt = get_plan()->get_stmt())
|| OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpected NULL", K(ret), K(get_plan()), K(stmt), K(child));
} else if (OB_FAIL(child->get_pushdown_op(log_op_def::LOG_DISTINCT, op))) {
LOG_WARN("failed to get push down distinct", K(ret));
} else if (OB_FAIL(stmt->get_qb_name(qb_name))) {
LOG_WARN("fail to get qb_name", K(ret), K(stmt->get_stmt_id()));
} else if (NULL != op &&
OB_FAIL(BUF_PRINTF("%s%s(@\"%.*s\")",
ObQueryHint::get_outline_indent(plan_text.is_oneline_),
ObHint::get_hint_name(T_DISTINCT_PUSHDOWN),
qb_name.length(),
qb_name.ptr()))) {
LOG_WARN("fail to print buffer", K(ret), K(buf), K(buf_len), K(pos));
} else if (HASH_AGGREGATE == algo_ &&
OB_FAIL(BUF_PRINTF("%s%s(@\"%.*s\")",
ObQueryHint::get_outline_indent(plan_text.is_oneline_),
ObHint::get_hint_name(T_USE_HASH_DISTINCT),
qb_name.length(),
qb_name.ptr()))) {
LOG_WARN("fail to print buffer", K(ret), K(buf), K(buf_len), K(pos));
} else {/*do nothing*/}
return ret;
}
int ObLogDistinct::print_used_hint(PlanText &plan_text)
{
int ret = OB_SUCCESS;
if (is_push_down()) {
/* print outline in top distinct */
} else if (OB_ISNULL(get_plan())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpected NULL", K(ret), K(get_plan()));
} else {
const ObHint *use_hash = get_plan()->get_log_plan_hint().get_normal_hint(T_USE_HASH_DISTINCT);
const ObHint *pushdown = get_plan()->get_log_plan_hint().get_normal_hint(T_DISTINCT_PUSHDOWN);
if (NULL != use_hash) {
bool match_hint = (HASH_AGGREGATE == algo_ && use_hash->is_enable_hint())
|| (MERGE_AGGREGATE == algo_ && use_hash->is_disable_hint());
if (match_hint && OB_FAIL(use_hash->print_hint(plan_text))) {
LOG_WARN("failed to print used hint for group by", K(ret), K(*use_hash));
}
}
if (OB_SUCC(ret) && NULL != pushdown) {
const ObLogicalOperator *child = NULL;
const ObLogicalOperator *op = NULL;
if (OB_ISNULL(child = get_child(ObLogicalOperator::first_child))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpected NULL", K(ret), K(child));
} else if (OB_FAIL(child->get_pushdown_op(log_op_def::LOG_DISTINCT, op))) {
LOG_WARN("failed to get push down distinct", K(ret));
} else {
bool match_hint = NULL == op ? pushdown->is_disable_hint()
: pushdown->is_enable_hint();
if (match_hint && OB_FAIL(pushdown->print_hint(plan_text))) {
LOG_WARN("failed to print used hint for group by", K(ret), K(*pushdown));
}
}
}
}
return ret;
}
int ObLogDistinct::get_card_without_filter(double &card)
{
int ret = OB_SUCCESS;
card = get_total_ndv();
return ret;
}
}
}