Multiple $regex using $and in MongoDB

Question

I have some collection with the next records:

{
    "_id" : ObjectId("52b18fb2a21351b2bb29dfc7"),
    "title" : "aaa"
}
{
    "_id" : ObjectId("52b18fd0d17d7f69e078f7b7"),
    "title" : "bbb"
}
{
    "_id" : ObjectId("52b18fd3d17d7f69e078f7b8"),
    "title" : "ccc"
}

Next query gives as a result 1 records (with title="aaa") as we expected:

db.test.find({
     {title:{$regex:'aaa'}}
})

But when we use complex condition for $and we got something unexpected:

db.test.find({
    $and: [
        {title:{$regex:'aaa'}},
        {title:{$regex:'bbb'}}
    ]
})

I need query exactly in this case because I'm going to use selection with stop-words, for example:

db.test.find({
    $and: [
        {title:{$regex:'aaa'}},
        {title:{$regex:'bbb'}},
        {title:{$not:/bbb/i}},
    ]
})

Using query that above, I expecting only one field in result (with title="aaa").

I have idea how to solve this issue using aggregate, but I hope there is another way how to solve it.

Thanks!

Answer 1

Simply build proper regex

pattern "/A AND B/"
pattern "/NOT (NOT A OR NOT B)/"

Regex:

"/^(^A|^B)/"

Or this one

/(?=.*word1)(?=.*word2)/

Answer 2

Well, tested using another data and got expected result:

/* 0 */
{
    "_id" : ObjectId("52b18fb2a21351b2bb29dfc7"),
    "title" : "aaa"
}

/* 1 */
{
    "_id" : ObjectId("52b18fd0d17d7f69e078f7b7"),
    "title" : "bbb"
}

/* 2 */
{
    "_id" : ObjectId("52b18fd3d17d7f69e078f7b8"),
    "title" : "ccc"
}

/* 3 */
{
    "_id" : ObjectId("52b19606d17d7f69e078f7b9"),
    "title" : "aaa test"
}

/* 4 */
{
    "_id" : ObjectId("52b19624d17d7f69e078f7ba"),
    "title" : "aaa test wel"
}

Query:

db.test.find({
    $and: [
        {title:{$regex:'aa'}},
        {title:{$regex:'t'}},
        {title:{$not:/wel/}}
    ]
})

Response:

/* 0 */
{
    "_id" : ObjectId("52b19606d17d7f69e078f7b9"),
    "title" : "aaa test"
}

Perhaps, that issue reproducing only when title and conditions contains cyrillic symbols. Going to to reproduce it now..