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50 lines
1.4 KiB
C++
50 lines
1.4 KiB
C++
// dbhelpers.cpp
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/**
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* Copyright (C) 2008 10gen Inc.
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*
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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 Affero General Public License, version 3,
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* as published by the Free Software Foundation.
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*
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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 Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "stdafx.h"
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#include "db.h"
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#include "dbhelpers.h"
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#include "query.h"
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/* Get the first object from a collection. Generally only useful if the collection
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only ever has a single object -- which is a "singleton collection.
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Returns: true if object exists.
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*/
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bool getSingleton(const char *ns, BSONObj& result) {
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DBContext context(ns);
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auto_ptr<Cursor> c = DataFileMgr::findAll(ns);
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if( !c->ok() )
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return false;
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result = c->current();
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return true;
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}
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void putSingleton(const char *ns, BSONObj obj) {
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DBContext context(ns);
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stringstream ss;
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updateObjects(ns, obj, /*pattern=*/emptyObj, /*upsert=*/true, ss);
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}
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void emptyCollection(const char *ns) {
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DBContext context(ns);
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deleteObjects(ns, emptyObj, false);
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}
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