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[FEAT MERGE] [CP] Improve the rowcount estimation

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Co-authored-by: akaError <lzg020616@163.com>
This commit is contained in:
xianyu-w
2024-02-09 19:58:18 +00:00
committed by ob-robot
parent da232dc640
commit dc32079645
70 changed files with 5953 additions and 3722 deletions
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6
src/sql/optimizer/ob_log_distinct.cpp
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@ -161,6 +161,8 @@ int ObLogDistinct::do_re_est_cost(EstimateCostInfo &param, double &card, double
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 &&
@ -170,9 +172,13 @@ int ObLogDistinct::do_re_est_cost(EstimateCostInfo &param, double &card, double
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 {