diff options
Diffstat (limited to 'src/mongo/db/commands/count_cmd.cpp')
| -rw-r--r-- | src/mongo/db/commands/count_cmd.cpp | 229 |
1 files changed, 119 insertions, 110 deletions
diff --git a/src/mongo/db/commands/count_cmd.cpp b/src/mongo/db/commands/count_cmd.cpp index 7f4e0bf3a65..91838325936 100644 --- a/src/mongo/db/commands/count_cmd.cpp +++ b/src/mongo/db/commands/count_cmd.cpp @@ -44,121 +44,130 @@ namespace mongo { namespace { - using std::unique_ptr; - using std::string; - using std::stringstream; - - /** - * Implements the MongoD side of the count command. - */ - class CmdCount : public Command { - public: - virtual bool isWriteCommandForConfigServer() const { return false; } - CmdCount() : Command("count") { } - virtual bool slaveOk() const { - // ok on --slave setups - return repl::getGlobalReplicationCoordinator()->getSettings().slave == repl::SimpleSlave; +using std::unique_ptr; +using std::string; +using std::stringstream; + +/** + * Implements the MongoD side of the count command. + */ +class CmdCount : public Command { +public: + virtual bool isWriteCommandForConfigServer() const { + return false; + } + CmdCount() : Command("count") {} + virtual bool slaveOk() const { + // ok on --slave setups + return repl::getGlobalReplicationCoordinator()->getSettings().slave == repl::SimpleSlave; + } + virtual bool slaveOverrideOk() const { + return true; + } + virtual bool maintenanceOk() const { + return false; + } + virtual bool adminOnly() const { + return false; + } + virtual void help(stringstream& help) const { + help << "count objects in collection"; + } + virtual void addRequiredPrivileges(const std::string& dbname, + const BSONObj& cmdObj, + std::vector<Privilege>* out) { + ActionSet actions; + actions.addAction(ActionType::find); + out->push_back(Privilege(parseResourcePattern(dbname, cmdObj), actions)); + } + + virtual Status explain(OperationContext* txn, + const std::string& dbname, + const BSONObj& cmdObj, + ExplainCommon::Verbosity verbosity, + BSONObjBuilder* out) const { + auto request = CountRequest::parseFromBSON(dbname, cmdObj); + if (!request.isOK()) { + return request.getStatus(); } - virtual bool slaveOverrideOk() const { return true; } - virtual bool maintenanceOk() const { return false; } - virtual bool adminOnly() const { return false; } - virtual void help( stringstream& help ) const { help << "count objects in collection"; } - virtual void addRequiredPrivileges(const std::string& dbname, - const BSONObj& cmdObj, - std::vector<Privilege>* out) { - ActionSet actions; - actions.addAction(ActionType::find); - out->push_back(Privilege(parseResourcePattern(dbname, cmdObj), actions)); + + // Acquire the db read lock. + AutoGetCollectionForRead ctx(txn, request.getValue().getNs()); + Collection* collection = ctx.getCollection(); + + // Prevent chunks from being cleaned up during yields - this allows us to only check the + // version on initial entry into count. + RangePreserver preserver(collection); + + PlanExecutor* rawExec; + Status getExecStatus = getExecutorCount(txn, + collection, + request.getValue(), + true, // explain + PlanExecutor::YIELD_AUTO, + &rawExec); + if (!getExecStatus.isOK()) { + return getExecStatus; } - virtual Status explain(OperationContext* txn, - const std::string& dbname, - const BSONObj& cmdObj, - ExplainCommon::Verbosity verbosity, - BSONObjBuilder* out) const { - - auto request = CountRequest::parseFromBSON(dbname, cmdObj); - if (!request.isOK()) { - return request.getStatus(); - } - - // Acquire the db read lock. - AutoGetCollectionForRead ctx(txn, request.getValue().getNs()); - Collection* collection = ctx.getCollection(); - - // Prevent chunks from being cleaned up during yields - this allows us to only check the - // version on initial entry into count. - RangePreserver preserver(collection); - - PlanExecutor* rawExec; - Status getExecStatus = getExecutorCount(txn, - collection, - request.getValue(), - true, // explain - PlanExecutor::YIELD_AUTO, - &rawExec); - if (!getExecStatus.isOK()) { - return getExecStatus; - } - - unique_ptr<PlanExecutor> exec(rawExec); - - Explain::explainStages(exec.get(), verbosity, out); - return Status::OK(); + unique_ptr<PlanExecutor> exec(rawExec); + + Explain::explainStages(exec.get(), verbosity, out); + return Status::OK(); + } + + virtual bool run(OperationContext* txn, + const string& dbname, + BSONObj& cmdObj, + int, + string& errmsg, + BSONObjBuilder& result) { + auto request = CountRequest::parseFromBSON(dbname, cmdObj); + if (!request.isOK()) { + return appendCommandStatus(result, request.getStatus()); } - virtual bool run(OperationContext* txn, - const string& dbname, - BSONObj& cmdObj, - int, string& errmsg, - BSONObjBuilder& result) { - - auto request = CountRequest::parseFromBSON(dbname, cmdObj); - if (!request.isOK()) { - return appendCommandStatus(result, request.getStatus()); - } - - AutoGetCollectionForRead ctx(txn, request.getValue().getNs()); - Collection* collection = ctx.getCollection(); - - // Prevent chunks from being cleaned up during yields - this allows us to only check the - // version on initial entry into count. - RangePreserver preserver(collection); - - PlanExecutor* rawExec; - Status getExecStatus = getExecutorCount(txn, - collection, - request.getValue(), - false, // !explain - PlanExecutor::YIELD_AUTO, - &rawExec); - if (!getExecStatus.isOK()) { - return appendCommandStatus(result, getExecStatus); - } - - unique_ptr<PlanExecutor> exec(rawExec); - - // Store the plan summary string in CurOp. - if (NULL != CurOp::get(txn)) { - CurOp::get(txn)->debug().planSummary = Explain::getPlanSummary(exec.get()); - } - - Status execPlanStatus = exec->executePlan(); - if (!execPlanStatus.isOK()) { - return appendCommandStatus(result, execPlanStatus); - } - - // Plan is done executing. We just need to pull the count out of the root stage. - invariant(STAGE_COUNT == exec->getRootStage()->stageType()); - CountStage* countStage = static_cast<CountStage*>(exec->getRootStage()); - const CountStats* countStats = - static_cast<const CountStats*>(countStage->getSpecificStats()); - - result.appendNumber("n", countStats->nCounted); - return true; + AutoGetCollectionForRead ctx(txn, request.getValue().getNs()); + Collection* collection = ctx.getCollection(); + + // Prevent chunks from being cleaned up during yields - this allows us to only check the + // version on initial entry into count. + RangePreserver preserver(collection); + + PlanExecutor* rawExec; + Status getExecStatus = getExecutorCount(txn, + collection, + request.getValue(), + false, // !explain + PlanExecutor::YIELD_AUTO, + &rawExec); + if (!getExecStatus.isOK()) { + return appendCommandStatus(result, getExecStatus); } - } cmdCount; + unique_ptr<PlanExecutor> exec(rawExec); + + // Store the plan summary string in CurOp. + if (NULL != CurOp::get(txn)) { + CurOp::get(txn)->debug().planSummary = Explain::getPlanSummary(exec.get()); + } + + Status execPlanStatus = exec->executePlan(); + if (!execPlanStatus.isOK()) { + return appendCommandStatus(result, execPlanStatus); + } + + // Plan is done executing. We just need to pull the count out of the root stage. + invariant(STAGE_COUNT == exec->getRootStage()->stageType()); + CountStage* countStage = static_cast<CountStage*>(exec->getRootStage()); + const CountStats* countStats = + static_cast<const CountStats*>(countStage->getSpecificStats()); + + result.appendNumber("n", countStats->nCounted); + return true; + } + +} cmdCount; -} // namespace -} // namespace mongo +} // namespace +} // namespace mongo |