Imported Upstream version 2.6.11upstream/2.6.11

1 files changed, 133 insertions, 0 deletions

diff --git a/src/mongo/db/query/single_solution_runner.cpp b/src/mongo/db/query/single_solution_runner.cpp
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+++ b/src/mongo/db/query/single_solution_runner.cpp
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+/**
+ *    Copyright 2013 MongoDB 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.
+ */
+
+#include "mongo/db/query/single_solution_runner.h"
+
+#include "mongo/db/diskloc.h"
+#include "mongo/db/jsobj.h"
+#include "mongo/db/exec/plan_stage.h"
+#include "mongo/db/exec/working_set.h"
+#include "mongo/db/query/canonical_query.h"
+#include "mongo/db/query/explain_plan.h"
+#include "mongo/db/query/type_explain.h"
+#include "mongo/db/query/plan_executor.h"
+#include "mongo/db/query/query_solution.h"
+
+namespace mongo {
+
+    SingleSolutionRunner::SingleSolutionRunner(const Collection* collection,
+                                               CanonicalQuery* canonicalQuery,
+                                               QuerySolution* soln,
+                                               PlanStage* root,
+                                               WorkingSet* ws)
+        : _collection( collection ),
+          _canonicalQuery(canonicalQuery),
+          _solution(soln),
+          _exec(new PlanExecutor(ws, root)) { }
+
+    SingleSolutionRunner::~SingleSolutionRunner() { }
+
+    Runner::RunnerState SingleSolutionRunner::getNext(BSONObj* objOut, DiskLoc* dlOut) {
+        return _exec->getNext(objOut, dlOut);
+        // TODO: I'm not convinced we want to cache this run.  What if it's a collscan solution
+        // and the user adds an index later?  We don't want to reach for this.  But if solving
+        // the query is v. hard, we do want to cache it.  Maybe we can remove single solution
+        // cache entries when we build an index?
+    }
+
+    bool SingleSolutionRunner::isEOF() {
+        return _exec->isEOF();
+    }
+
+    void SingleSolutionRunner::saveState() {
+        _exec->saveState();
+    }
+
+    bool SingleSolutionRunner::restoreState() {
+        return _exec->restoreState();
+    }
+
+    void SingleSolutionRunner::setYieldPolicy(Runner::YieldPolicy policy) {
+        _exec->setYieldPolicy(policy);
+    }
+
+    void SingleSolutionRunner::invalidate(const DiskLoc& dl, InvalidationType type) {
+        _exec->invalidate(dl, type);
+    }
+
+    const std::string& SingleSolutionRunner::ns() {
+        return _canonicalQuery->getParsed().ns();
+    }
+
+    void SingleSolutionRunner::kill() {
+        _exec->kill();
+        _collection = NULL;
+    }
+
+    Status SingleSolutionRunner::getInfo(TypeExplain** explain,
+                                         PlanInfo** planInfo) const {
+        if (NULL != explain) {
+            verify(_exec.get());
+
+            scoped_ptr<PlanStageStats> stats(_exec->getStats());
+            if (NULL == stats.get()) {
+                return Status(ErrorCodes::InternalError, "no stats available to explain plan");
+            }
+
+            Status status = explainPlan(*stats, explain, true /* full details */);
+            if (!status.isOK()) {
+                return status;
+            }
+
+            // Fill in explain fields that are accounted by on the runner level.
+            TypeExplain* chosenPlan = NULL;
+            explainPlan(*stats, &chosenPlan, false /* no full details */);
+            if (chosenPlan) {
+                (*explain)->addToAllPlans(chosenPlan);
+            }
+            (*explain)->setNScannedObjectsAllPlans((*explain)->getNScannedObjects());
+            (*explain)->setNScannedAllPlans((*explain)->getNScanned());
+
+            // _solution could be NULL in certain cases such as when QueryOption_OplogReplay
+            // is enabled in the query flags.
+            if (_solution) {
+                (*explain)->setIndexFilterApplied(_solution->indexFilterApplied);
+            }
+        }
+        else if (NULL != planInfo) {
+            if (NULL == _solution.get()) {
+                return Status(ErrorCodes::InternalError,
+                              "no solution available for plan info");
+            }
+            getPlanInfo(*_solution, planInfo);
+        }
+
+        return Status::OK();
+    }
+
+} // namespace mongo