问题
I want to query something with SQL\'s like query:
SELECT * FROM users WHERE name LIKE \'%m%\'
How to do I achieve the same in MongoDB? I can\'t find an operator for like in the documentation.
回答1:
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 Regexp's '.*'), 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 info on regular expressions refer to this link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
回答2:
db.users.insert({name: 'paulo'})
db.users.insert({name: 'patric'})
db.users.insert({name: 'pedro'})
db.users.find({name: /a/}) //like '%a%'
out: paulo, patric
db.users.find({name: /^pa/}) //like 'pa%'
out: paulo, patric
db.users.find({name: /ro$/}) //like '%ro'
out: pedro
回答3:
In
- PyMongo using Python
- Mongoose using Node.js
- Jongo, using Java
- mgo, using Go
you can do:
db.users.find({'name': {'$regex': 'sometext'}})
回答4:
In PHP, you could use following code:
$collection->find(array('name'=> array('$regex' => 'm'));
回答5:
You would use regex for that in mongo.
e.g: db.users.find({"name": /^m/})
回答6:
There are already many answers. I am giving different types of requirements and solutions for string search with regex.
You can do with regex which contain word i.e like. Also you can use $options => i for case insensitive search
Contains string
db.collection.find({name:{'$regex' : 'string', '$options' : 'i'}})
Doesn't Contains string only with regex
db.collection.find({name:{'$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 this as a bookmark, and a reference for any other alterations you may need.
回答7:
You have 2 choices:
db.users.find({"name": /string/})
or
db.users.find({"name": {"$regex": "string", "$options": "i"}})
On 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 regular expression as you want.
Enjoy!
回答8:
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', $options: 'i' } } );
Also, you can write this:
db.collection.find( { field: new RegExp('acme.*corp', 'i') } );
回答9:
Already u got the answers but to match regex with case insensitivity
You could use the following query
db.users.find ({ "name" : /m/i } ).pretty()
The i in the /m/i indicates case insensitivity and .pretty() provides a more pretty output
回答10:
For Mongoose in Node.js
db.users.find({'name': {'$regex': '.*sometext.*'}})
回答11:
You can use the new feature of 2.6 mongodb:
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"
}
});
回答12:
For PHP mongo Like.
I had several issues with php mongo like. i found that concatenating the regex params helps in some situations PHP mongo find field starts with. I figured I would post on here to contribute to the more popular thread
e.g
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($name))]);
output: (joe, john, jason)
回答13:
In nodejs project and use mongoose use Like query
var User = mongoose.model('User');
var searchQuery={};
searchQuery.email = req.query.email;
searchQuery.name = {$regex: req.query.name, $options: 'i'};
User.find(searchQuery, function(error, user) {
if(error || user === null) {
return res.status(500).send(error);
}
return res.status(200).send(user);
});
回答14:
With MongoDB Compass, you need to use the strict mode syntax, as such:
{ "text": { "$regex": "^Foo.*", "$options": "i" } }
(In MongoDB Compass, it's important that you use " instead of ')
回答15:
In SQL, the ‘like’ query is looks like this :
select * from users where name like '%m%'
In MongoDB console, it looks like this :
db.users.find({"name": /m/}) // Not JSON formatted
db.users.find({"name": /m/}).pretty() // JSON formatted
In addion pretty() method will in all the places where produce formatted JSON structure which is more readable.
回答16:
Regex are expensive are process.
Another way is to create an index of text and then search it using $search.
Create a text Index of fields you want to make searchable:
db.collection.createIndex({name: 'text', otherField: 'text'});
Search for a string in text index:
db.collection.find({
'$text'=>{'$search': "The string"}
})
回答17:
You can use where statement to build any JS script:
db.myCollection.find( { $where: "this.name.toLowerCase().indexOf('m') >= 0" } );
Reference: http://docs.mongodb.org/manual/reference/operator/where/
回答18:
In Go and the mgo driver:
Collection.Find(bson.M{"name": bson.RegEx{"m", ""}}).All(&result)
where result is the struct instance of the sought after type
回答19:
Use regular expressions matching as below. The 'i' shows case insensitivity.
var collections = mongoDatabase.GetCollection("Abcd");
var queryA = Query.And(
Query.Matches("strName", new BsonRegularExpression("ABCD", "i")),
Query.Matches("strVal", new BsonRegularExpression("4121", "i")));
var queryB = Query.Or(
Query.Matches("strName", new BsonRegularExpression("ABCD","i")),
Query.Matches("strVal", new BsonRegularExpression("33156", "i")));
var getA = collections.Find(queryA);
var getB = collections.Find(queryB);
回答20:
Using template literals with variables also works:
{"firstname": {$regex : `^${req.body.firstname}.*` , $options: 'si' }}
回答21:
Like Query would be as shown below
db.movies.find({title: /.*Twelve Monkeys.*/}).sort({regularizedCorRelation : 1}).limit(10);
for scala ReactiveMongo api,
val query = BSONDocument("title" -> BSONRegex(".*"+name+".*", "")) //like
val sortQ = BSONDocument("regularizedCorRelation" -> BSONInteger(1))
val cursor = collection.find(query).sort(sortQ).options(QueryOpts().batchSize(10)).cursor[BSONDocument]
回答22:
It seems that there are reasons for using both the javascript /regex_pattern/ pattern as well as the mongo {'$regex': 'regex_pattern'} pattern. See: MongoBD RegEx Syntax Restrictions
This is not a complete RegEx 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" }
回答23:
If you are using Spring-Data Mongodb You can do this in this way:
String tagName = "m";
Query query = new Query();
query.limit(10);
query.addCriteria(Criteria.where("tagName").regex(tagName));
回答24:
As Mongo shell support regex, that's completely possible.
db.users.findOne({"name" : /.*sometext.*/});
If we want the query to be case-insensitive, we can use "i" option, like shown below:
db.users.findOne({"name" : /.*sometext.*/i});
回答25:
If you want 'Like' search in mongo then you should go with $regex by using this query will be
db.product.find({name:{$regex:/m/i}})
for more you can read the documentation as well. https://docs.mongodb.com/manual/reference/operator/query/regex/
回答26:
I found a free tool to translate MYSQL queries to MongoDB. http://www.querymongo.com/ I checked with several queries. as i see almost all them are correct. According to that, The answer is
db.users.find({
"name": "%m%"
});
回答27:
Use aggregation substring search (with index!!!):
db.collection.aggregate([{
$project : {
fieldExists : {
$indexOfBytes : ['$field', 'string']
}
}
}, {
$match : {
fieldExists : {
$gt : -1
}
}
}, {
$limit : 5
}
]);
回答28:
MongoRegex has been deprecated.
Use MongoDB\BSON\Regex
$regex = new MongoDB\BSON\Regex ( '^m');
$cursor = $collection->find(array('users' => $regex));
//iterate through the cursor
回答29:
db.customer.find({"customerid": {"$regex": "CU_00000*", "$options": "i"}}).pretty()
When we are searching for string patterns, always it is better to use the above pattern as when we are not sure about case. Hope that helps!!!
回答30:
String deepakparmar, dipak, parmar
db.getCollection('yourdb').find({"name":/^dee/})
ans deepakparmar
db.getCollection('yourdb').find({"name":/d/})
ans deepakparmar, dipak
db.getCollection('yourdb').find({"name":/mar$/})
ans deepakparmar, parmar
来源：https://stackoverflow.com/questions/3305561/how-to-query-mongodb-with-like