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author | Hari Khalsa <hkhalsa@10gen.com> | 2013-09-18 11:57:21 -0400 |
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committer | Hari Khalsa <hkhalsa@10gen.com> | 2013-09-18 16:42:20 -0400 |
commit | 311ebc33f399b555309ee6eba04af8c605108529 (patch) | |
tree | be50e3cfea0c124759ded943a5d1c7cc5a79910b /src/mongo/db/exec/projection.h | |
parent | de25d5b966fae434669df47b41c076445d2303f6 (diff) | |
download | mongo-311ebc33f399b555309ee6eba04af8c605108529.tar.gz |
SERVER-10026 enumeration as strategies, bug fixes galore, build plans
Diffstat (limited to 'src/mongo/db/exec/projection.h')
-rw-r--r-- | src/mongo/db/exec/projection.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/src/mongo/db/exec/projection.h b/src/mongo/db/exec/projection.h new file mode 100644 index 00000000000..ade2bbfab84 --- /dev/null +++ b/src/mongo/db/exec/projection.h @@ -0,0 +1,71 @@ +/** + * Copyright (C) 2013 10gen Inc. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License, version 3, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * As a special exception, the copyright holders give permission to link the + * code of portions of this program with the OpenSSL library under certain + * conditions as described in each individual source file and distribute + * linked combinations including the program with the OpenSSL library. You + * must comply with the GNU Affero General Public License in all respects for + * all of the code used other than as permitted herein. If you modify file(s) + * with this exception, you may extend this exception to your version of the + * file(s), but you are not obligated to do so. If you do not wish to do so, + * delete this exception statement from your version. If you delete this + * exception statement from all source files in the program, then also delete + * it in the license file. + */ + +#pragma once + +#include "mongo/db/diskloc.h" +#include "mongo/db/exec/plan_stage.h" +#include "mongo/db/exec/query_projection.h" +#include "mongo/db/jsobj.h" +#include "mongo/db/matcher/expression.h" + +namespace mongo { + + /** + * This stage computes a projection. + */ + class ProjectionStage : public PlanStage { + public: + ProjectionStage(QueryProjection* projection, WorkingSet* ws, PlanStage* child, + const MatchExpression* filter); + virtual ~ProjectionStage(); + + virtual bool isEOF(); + virtual StageState work(WorkingSetID* out); + + virtual void prepareToYield(); + virtual void recoverFromYield(); + virtual void invalidate(const DiskLoc& dl); + + PlanStageStats* getStats(); + + private: + scoped_ptr<QueryProjection> _projection; + + // _ws is not owned by us. + WorkingSet* _ws; + scoped_ptr<PlanStage> _child; + + // The filter is not owned by us. + const MatchExpression* _filter; + + // Stats + CommonStats _commonStats; + }; + +} // namespace mongo |