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[CP] Enable re_est_cost for prefix sort

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This commit is contained in:
2149
2024-01-22 11:47:07 +00:00
committed by ob-robot
parent b2ddd6a131
commit 240e147747
2 changed files with 37 additions and 3 deletions
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39
src/sql/optimizer/ob_log_sort.cpp
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@ -378,11 +378,44 @@ int ObLogSort::do_re_est_cost(EstimateCostInfo &param, double &card, double &op_
card = param.need_row_count_;
}
ObLogicalOperator *child = get_child(ObLogicalOperator::first_child);
if (OB_ISNULL(child)) {
if (OB_ISNULL(child) || OB_ISNULL(get_plan()) || OB_ISNULL(get_stmt())
|| OB_ISNULL(get_stmt()->get_query_ctx())) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("get unexpected null", K(ret));
} else if (OB_FALSE_IT(param.need_row_count_ = -1)) {
//limit N在sort算子被阻塞
} else if (get_stmt()->get_query_ctx()->optimizer_features_enable_version_ < COMPAT_VERSION_4_2_1_BP4) {
param.need_row_count_ = -1;
} else if (-1 == param.need_row_count_) {
//do nothing
} else if (!is_prefix_sort()) {
param.need_row_count_ = -1;
} else {
ObSEArray<ObRawExpr*, 4> prefix_ordering;
for (int64_t i = 0; OB_SUCC(ret) && i < get_prefix_pos(); ++i) {
if (OB_FAIL(prefix_ordering.push_back(sort_keys_.at(i).expr_))) {
LOG_WARN("push back order key expr failed", K(ret));
}
}
if (OB_SUCC(ret)) {
double prefix_ndv = 0.0;
if (OB_FAIL(ObOptSelectivity::calculate_distinct(get_plan()->get_update_table_metas(),
get_plan()->get_selectivity_ctx(),
prefix_ordering,
child->get_card(),
prefix_ndv))) {
LOG_WARN("failed to calculate distinct", K(ret));
} else if (OB_UNLIKELY(std::fabs(prefix_ndv) < 1.0)) {
param.need_row_count_ = -1;
} else {
double num_rows_per_group = child->get_card() / prefix_ndv;
double num_groups = std::ceil(param.need_row_count_ / num_rows_per_group);
param.need_row_count_ = num_groups * num_rows_per_group;
if (param.need_row_count_ >= child->get_card()) {
param.need_row_count_ = -1;
}
}
}
}
if (OB_FAIL(ret)) {
} else if (OB_FAIL(SMART_CALL(child->re_est_cost(param, child_card, child_cost)))) {
LOG_WARN("failed to re est cost", K(ret));
} else if (OB_FAIL(inner_est_cost(parallel, child_card, double_topn_count, op_cost))) {