How to query MongoDB with "like"

Asked 2023-09-21 08:08:36 View 213,580

I want to query something with SQL's like query:

SELECT * FROM users  WHERE name LIKE '%m%'

How can I achieve the same in MongoDB? I can't find an operator for like in the documentation.

  • see mongodb's docs: Advanced Queries -- Regular expressions mongodb.org/display/DOCS/… - anyone
  • I seriously suggest taking a look at MongoDB Atlas Search, as it is much more resource efficient and feature rich for "like"-like queries that $text or $regex - anyone

Answers

That would have to be:

db.users.find({"name": /.*m.*/})

Or, similar:

db.users.find({"name": /m/})

You're looking for something that contains "m" somewhere (SQL's '%' operator is equivalent to regular expressions' '.*'), not something that has "m" anchored to the beginning of the string.

Note: MongoDB uses regular expressions which are more powerful than "LIKE" in SQL. With regular expressions you can create any pattern that you imagine.

For more information on regular expressions, refer to Regular expressions (MDN).

Answered   2023-09-21 08:08:36

  • is searching by regex expensive? - anyone
  • Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what's happening. - anyone
  • When not anchored to the beginning of the string, it is somewhat expensive. But then again, so is a LIKE query in SQL. - anyone
  • I would add regex i javascript db.users.find({ "name": { $regex: /m/i } }) - anyone
  • It is worth mentioning that if you want to use it from Node app and you want a dynamic search, you can use: users.find({"name": new RegExp('.*' + searchVariable + '.*')}) So, this way you can use it with other operators like $in, $nin, etc. - anyone
db.users.insert({name: 'patrick'})
db.users.insert({name: 'petra'})
db.users.insert({name: 'pedro'})

Therefore:

For:

db.users.find({name: /a/})  // Like '%a%'

Output: patrick, petra

For:

db.users.find({name: /^pa/}) // Like 'pa%'

Output: patrick

For:

db.users.find({name: /ro$/}) // Like '%ro'

Output: pedro

Answered   2023-09-21 08:08:36

  • You know why you have so many upvotes? Because the docs deserve equal many downvotes! Thank you - anyone
  • To search for strings with forward slashes in them, just escape it like so: db.users.find({name: /^path\/to\/something/}) // Like 'path/to/something%' - anyone
  • Performance wise, $regex is not the best approach... - anyone

In

  • PyMongo using Python
  • Mongoose using Node.js
  • Jongo, using Java
  • mgo, using Go

you can do:

db.users.find({'name': {'$regex': 'sometext'}})

Answered   2023-09-21 08:08:36

  • @TahirYasin if you're still wondering, case-insensitive search would be done like this: db.users.find({'name': {'$regex': 'sometext', '$options': 'i'}}) - anyone
  • this applies to the whole word, not to a part of the word. - anyone

In PHP, you could use the following code:

$collection->find(array('name'=> array('$regex' => 'm'));

Answered   2023-09-21 08:08:36

  • You can also specify the flags in the second item of the $regex array, like so: $collection->find(array('name'=> array('$regex' => 'm', '$options => 'i')); - anyone

Here are different types of requirements and solutions for string search with regular expressions.

You can do with a regular expression which contains a word, i.e., like. Also you can use $options => i for a case insensitive search.

Contains string

db.collection.find({name:{'$regex' : 'string', '$options' : 'i'}})

Doesn't contain string, only with a regular expression

db.collection.find({name:{'$regex' : '^((?!string).)*$', '$options' : 'i'}})

Exact case insensitive string

db.collection.find({name:{'$regex' : '^string$', '$options' : 'i'}})

Start with string

db.collection.find({name:{'$regex' : '^string', '$options' : 'i'}})

End with string

db.collection.find({name:{'$regex' : 'string$', '$options' : 'i'}})

Keep Regular Expressions Cheat Sheet as a bookmark, and a reference for any other alterations you may need.

Answered   2023-09-21 08:08:36

  • this is a later comment but, how can I use a variable in above example? like let name = 'john doe' . how can I implement name variable in regex? thanks - anyone

You would use a regular expression for that in MongoDB.

For example,

db.users.find({"name": /^m/})

Answered   2023-09-21 08:08:36

  • I think this only shows documents with a name value that starts with "m" - anyone
  • Important to remove quotes when you use regex, i.e. don't do "/^m/", just do /^m/ - anyone

You have two choices:

db.users.find({"name": /string/})

or

db.users.find({"name": {"$regex": "string", "$options": "i"}})

For the second one, you have more options, like "i" in options to find using case insensitive.

And about the "string", you can use like ".string." (%string%), or "string.*" (string%) and ".*string) (%string) for example. You can use a regular expression as you want.

Answered   2023-09-21 08:08:36

If using Node.js, it says that you can write this:

db.collection.find( { field: /acme.*corp/i } );

// Or
db.collection.find( { field: { $regex: 'acme.*corp', $options: 'i' } } );

Also, you can write this:

db.collection.find( { field: new RegExp('acme.*corp', 'i') } );

Answered   2023-09-21 08:08:36

  • Thanks @Eddy. Providing '$options: 'i'' with regex made refactoring process to easy for me. - anyone

Already you got the answers, but to match with a regular expression with case insensitivity, you could use the following query:

db.users.find ({ "name" : /m/i } ).pretty()

The i in the /m/i indicates case insensitivity and .pretty() provides a prettier output.

Answered   2023-09-21 08:08:36

For Mongoose in Node.js:

db.users.find({'name': {'$regex': '.*sometext.*'}})

Answered   2023-09-21 08:08:36

With MongoDB Compass, you need to use the strict mode syntax, as such:

{ "text": { "$regex": "^Foo.*", "$options": "i" } }

(In MongoDB Compass, it's important that you use " instead of ')

Answered   2023-09-21 08:08:36

  • This nearly drove me crazy much appreciated, and why can't they give documentation or examples on doing things like this for Compass. I couldn't even find documentation on the strict mode syntax for Compass. - anyone

In MongoDb, can use like using MongoDb reference operator regular expression(regex).

For Same Ex.

MySQL - SELECT * FROM users  WHERE name LIKE '%m%'

MongoDb

    1) db.users.find({ "name": { "$regex": "m", "$options": "i" } })

    2) db.users.find({ "name": { $regex: new RegExp("m", 'i') } })

    3) db.users.find({ "name": { $regex:/m/i } })

    4) db.users.find({ "name": /mail/ })

    5) db.users.find({ "name": /.*m.*/ })

MySQL - SELECT * FROM users  WHERE name LIKE 'm%'

MongoDb Any of Above with /^String/

    6) db.users.find({ "name": /^m/ })

MySQL - SELECT * FROM users  WHERE name LIKE '%m'

MongoDb Any of Above with /String$/

    7) db.users.find({ "name": /m$/ })

Answered   2023-09-21 08:08:36

  • It becomes extremely slow on large datasets just FYI. And there's no way to know what the score is. - anyone

You can use the new feature of MongoDB 2.6:

db.foo.insert({desc: "This is a string with text"});
db.foo.insert({desc:"This is a another string with Text"});
db.foo.ensureIndex({"desc":"text"});
db.foo.find({
    $text:{
        $search:"text"
    }
});

Answered   2023-09-21 08:08:36

  • Note, AFAIK Mongodb's text searching works on whole words only by default, so this will match values like "This is a string with text", but not "This is a string with subtext". So it's not quite like sql's "LIKE" operator. - anyone

In a Node.js project and using Mongoose, use a like query:

var User = mongoose.model('User');

var searchQuery = {};
searchQuery.email = req.query.email;
searchQuery.name = {$regex: req.query.name, $options: 'i'};
User.find(searchQuery, function(error, user) {
                if(error || user === null) {
                    return res.status(500).send(error);
                }
                return res.status(200).send(user);
            });

Answered   2023-09-21 08:08:36

You can use a where statement to build any JavaScript script:

db.myCollection.find( { $where: "this.name.toLowerCase().indexOf('m') >= 0" } );

Reference: $where

Answered   2023-09-21 08:08:36

  • $where is highly inefficient. Do full collection scan :( - anyone

String yourdb={deepakparmar, dipak, parmar}

db.getCollection('yourdb').find({"name":/^dee/})

ans deepakparmar

db.getCollection('yourdb').find({"name":/d/})

ans deepakparmar, dipak

db.getCollection('yourdb').find({"name":/mar$/})

ans deepakparmar, parmar

Answered   2023-09-21 08:08:36

In Go and the mgo driver:

Collection.Find(bson.M{"name": bson.RegEx{"m", ""}}).All(&result)

where the result is the struct instance of the sought-after type.

Answered   2023-09-21 08:08:36

  • pls avoid unkeyed fields in literals, do bson:RegEx{Pattern:"m", Options:"i"} instead - anyone

In SQL, the ‘like’ query looks like this:

select * from users where name like '%m%'

In the MongoDB console, it looks like this:

db.users.find({"name": /m/})     // Not JSON formatted

db.users.find({"name": /m/}).pretty()  // JSON formatted

In addition, the pretty() method will produce a formatted JSON structure in all the places which is more readable.

Answered   2023-09-21 08:08:36

For PHP mongo Like.

I had several issues with PHP mongo like. I found that concatenating the regular expression parameters helps in some situations - PHP mongo find field starts with.

For example,

db()->users->insert(['name' => 'john']);
db()->users->insert(['name' => 'joe']);
db()->users->insert(['name' => 'jason']);

// starts with
$like_var = 'jo';
$prefix = '/^';
$suffix = '/';
$name = $prefix . $like_var . $suffix;
db()->users->find(['name' => array('$regex'=>new MongoRegex($name))]);
output: (joe, john)

// contains
$like_var = 'j';
$prefix = '/';
$suffix = '/';
$name = $prefix . $like_var . $suffix;
db()->users->find(['name' => array('$regex'=>new MongoRegex($name))]);

output: (joe, john, jason)

Answered   2023-09-21 08:08:36

Using template literals with variables also works:

{"firstname": {$regex : `^${req.body.firstname}.*` , $options: 'si' }}

Answered   2023-09-21 08:08:36

  • This doesn't work. Inputting names with special characters (for example () fails. - anyone
  • Are those valid variable names? Or do you mean: req.body.firstname = "John(Jimmy) Doe"? - anyone
  • The second one yes. - anyone

Regular expressions are expensive to process.

Another way is to create an index of text and then search it using $search.

Create a text index of fields you want to make searchable:

db.collection.createIndex({name: 'text', otherField: 'text'});

Search for a string in the text index:

db.collection.find({
  '$text'=>{'$search': "The string"}
})

Answered   2023-09-21 08:08:36

  • This doesn't work with partials. - anyone

Use regular expressions matching as below. The 'i' shows case insensitivity.

var collections = mongoDatabase.GetCollection("Abcd");

var queryA = Query.And(
         Query.Matches("strName", new BsonRegularExpression("ABCD", "i")), 
         Query.Matches("strVal", new BsonRegularExpression("4121", "i")));

var queryB = Query.Or(
       Query.Matches("strName", new BsonRegularExpression("ABCD","i")),
       Query.Matches("strVal", new BsonRegularExpression("33156", "i")));

var getA = collections.Find(queryA);
var getB = collections.Find(queryB);

Answered   2023-09-21 08:08:36

It seems that there are reasons for using both the JavaScript /regex_pattern/ pattern as well as the MongoDB {'$regex': 'regex_pattern'} pattern. See: MongoDB RegEx Syntax Restrictions

This is not a complete regular expression tutorial, but I was inspired to run these tests after seeing a highly voted ambiguous post above.

> ['abbbb','bbabb','bbbba'].forEach(function(v){db.test_collection.insert({val: v})})

> db.test_collection.find({val: /a/})
{ "val" : "abbbb" }
{ "val" : "bbabb" }
{ "val" : "bbbba" }

> db.test_collection.find({val: /.*a.*/})
{ "val" : "abbbb" }
{ "val" : "bbabb" }
{ "val" : "bbbba" }

> db.test_collection.find({val: /.+a.+/})
{ "val" : "bbabb" }

> db.test_collection.find({val: /^a/})
{ "val" : "abbbb" }

> db.test_collection.find({val: /a$/})
{ "val" : "bbbba" }

> db.test_collection.find({val: {'$regex': 'a$'}})
{ "val" : "bbbba" }

Answered   2023-09-21 08:08:36

A like query would be as shown below:

db.movies.find({title: /.*Twelve Monkeys.*/}).sort({regularizedCorRelation : 1}).limit(10);

For the Scala ReactiveMongo API,

val query = BSONDocument("title" -> BSONRegex(".*" + name + ".*", "")) // like
val sortQ = BSONDocument("regularizedCorRelation" -> BSONInteger(1))
val cursor = collection.find(query).sort(sortQ).options(QueryOpts().batchSize(10)).cursor[BSONDocument]

Answered   2023-09-21 08:08:36

If you are using Spring-Data MongoDB, you can do it in this way:

String tagName = "m";
Query query = new Query();
query.limit(10);
query.addCriteria(Criteria.where("tagName").regex(tagName));

Answered   2023-09-21 08:08:36

If you have a string variable, you must convert it to a regex, so MongoDB will use a like statement on it.

const name = req.query.title; //John
db.users.find({ "name": new Regex(name) });

Is the same result as:

db.users.find({"name": /John/})

Answered   2023-09-21 08:08:36

One way to find the result as with equivalent to a like query:

db.collection.find({name:{'$regex' : 'string', '$options' : 'i'}})

Where i is used for a case-insensitive fetch data.

Another way by which we can also get the result:

db.collection.find({"name":/aus/})

The above will provide the result which has the aus in the name containing aus.

Answered   2023-09-21 08:08:36

Use aggregation substring search (with index!!!):

db.collection.aggregate([{
        $project : {
            fieldExists : {
                $indexOfBytes : ['$field', 'string']
            }
        }
    }, {
        $match : {
            fieldExists : {
                $gt : -1
            }
        }
    }, {
        $limit : 5
    }
]);

Answered   2023-09-21 08:08:36

  • This might still be better than all these regex suggestions - but it still does a colscan. - anyone

You can query with a regular expression:

db.users.find({"name": /m/});

If the string is coming from the user, maybe you want to escape the string before using it. This will prevent literal chars from the user to be interpreted as regex tokens.

For example, searching the string "A." will also match "AB" if not escaped. You can use a simple replace to escape your string before using it. I made it a function for reusing:

function textLike(str) {
  var escaped = str.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, '\\$&');
  return new RegExp(escaped, 'i');
}

So now, the string becomes a case-insensitive pattern matching also the literal dot. Example:

>  textLike('A.');
<  /A\./i

Now we are ready to generate the regular expression on the go:

db.users.find({ "name": textLike("m") });

Answered   2023-09-21 08:08:36

If you want a 'like' search in MongoDB then you should go with $regex. By using it, the query will be:

db.product.find({name:{$regex:/m/i}})

For more, you can read the documentation as well - $regex

Answered   2023-09-21 08:08:36