55 lines
2.0 KiB
C++
55 lines
2.0 KiB
C++
/* Copyright (c) 2018, 2019, Alibaba and/or its affiliates. All rights reserved.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License, version 2.0,
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as published by the Free Software Foundation.
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This program is also distributed with certain software (including
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but not limited to OpenSSL) that is licensed under separate terms,
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as designated in a particular file or component or in included license
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documentation. The authors of MySQL hereby grant you an additional
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permission to link the program and your derivative works with the
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separately licensed software that they have included with MySQL.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License, version 2.0, for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
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#include "opt_hints_ext.h"
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void Sample_percentage_hint::print(const THD *, String *str) {
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std::stringstream ss;
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ss << "SAMPLE_PERCENTAGE"
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<< "(" << this->pct << ")";
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str->append(ss.str().c_str(), ss.str().length());
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}
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bool check_sample_semantic(LEX *lex) {
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DBUG_ASSERT(lex);
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auto select = lex->current_select();
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if (select == nullptr) {
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return false;
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}
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if (!lex->is_single_level_stmt() || select->where_cond() != nullptr ||
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select->having_cond() != nullptr || select->is_ordered() ||
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select->is_grouped() || select->explicit_limit) {
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return true;
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}
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if (select->table_list.elements != 1 ||
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select->table_list.first->index_hints != nullptr ||
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select->table_list.first->is_view_or_derived() ||
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select->table_list.first->is_table_function()) {
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return true;
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}
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return false;
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}
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