summaryrefslogtreecommitdiff
path: root/src/mongo/db/index/hash_access_method.cpp
blob: f160a9cfdbdc117eba6cd1eb6a221db507c4e928 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
/**
*    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.
*/

#include "mongo/db/index/hash_access_method.h"
#include "mongo/db/hasher.h"
#include "mongo/db/index/expression_keys_private.h"
#include "mongo/db/index/expression_params.h"

namespace mongo {

HashAccessMethod::HashAccessMethod(IndexCatalogEntry* btreeState, SortedDataInterface* btree)
    : IndexAccessMethod(btreeState, btree) {
    const IndexDescriptor* descriptor = btreeState->descriptor();

    // We can change these if the single-field limitation is lifted later.
    uassert(16763,
            "Currently only single field hashed index supported.",
            1 == descriptor->getNumFields());

    uassert(16764,
            "Currently hashed indexes cannot guarantee uniqueness. Use a regular index.",
            !descriptor->unique());

    ExpressionParams::parseHashParams(descriptor->infoObj(), &_seed, &_hashVersion, &_hashedField);

    _collator = btreeState->getCollator();
}

void HashAccessMethod::doGetKeys(const BSONObj& obj,
                                 GetKeysContext context,
                                 BSONObjSet* keys,
                                 MultikeyPaths* multikeyPaths) const {
    ExpressionKeysPrivate::getHashKeys(obj,
                                       _hashedField,
                                       _seed,
                                       _hashVersion,
                                       _descriptor->isSparse(),
                                       _collator,
                                       keys,
                                       (context == GetKeysContext::kRemovingKeys));
}

}  // namespace mongo