Checking if a field contains a string - mongodb

Question

I'm looking for an operator, which allows me to check, if the value of a field contains a certain string.
Something like:
db.users.findOne({$contains:{"username":"son"}})
Is that possible?

Answer 1

You can do it with the following code.
db.users.findOne({"username" : {$regex : "son"}});

Answer 2

As Mongo shell support regex, that's completely possible.
db.users.findOne({"username" : /.*son.*/});
If we want the query to be case-insensitive, we can use "i" option, like shown below:
db.users.findOne({"username" : /.*son.*/i});
See: http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-RegularExpressions

Answer 3

https://docs.mongodb.com/manual/reference/sql-comparison/
http://php.net/manual/en/mongo.sqltomongo.php
MySQL
SELECT * FROM users WHERE username LIKE "%Son%"
MongoDB
db.users.find({username:/Son/})

Answer 4

As of version 2.4, you can create a text index on the field(s) to search and use the $text operator for querying.
First, create the index:
db.users.createIndex( { "username": "text" } )
Then, to search:
db.users.find( { $text: { $search: "son" } } )
Benchmarks (~150K documents):
Regex (other answers) => 5.6-6.9 seconds
Text Search => .164-.201 seconds
Notes:
A collection can have only one text index. You can use a wildcard text index if you want to search any string field, like this: db.collection.createIndex( { "$**": "text" } ).
A text index can be large. It contains one index entry for each unique post-stemmed word in each indexed field for each document inserted.
A text index will take longer to build than a normal index.
A text index does not store phrases or information about the proximity of words in the documents. As a result, phrase queries will run much more effectively when the entire collection fits in RAM.

Answer 5

As this is one of the first hits in the search engines, and none of the above seems to work for MongoDB 3.x, here is one regex search that does work:
db.users.find( { 'name' : { '$regex' : yourvalue, '$options' : 'i' } } )
No need to create and extra index or alike.

Answer 6

Here's what you have to do if you are connecting MongoDB through Python
db.users.find({"username": {'$regex' : '.*' + 'Son' + '.*'}})
you may also use a variable name instead of 'Son' and therefore the string concatenation.

Answer 7

Simplest way to accomplish this task
If you want the query to be case-sensitive
db.getCollection("users").find({'username':/Son/})
If you want the query to be case-insensitive
db.getCollection("users").find({'username':/Son/i})

Answer 8

ideal answer its use index
i option for case-insensitive
db.users.findOne({"username" : new RegExp(search_value, 'i') });

Answer 9

This should do the work
db.users.find({ username: { $in: [ /son/i ] } });
The i is just there to prevent restrictions of matching single cases of letters.
You can check the $regex documentation on MongoDB documentation.
Here's a link: https://docs.mongodb.com/manual/reference/operator/query/regex/

Answer 10

I use this code and it work for search substring
db.users.find({key: { $regex: new RegExp(value, 'i')}})

Answer 11

If you need to do the search for more than one attribute you can use the $or. For example
Symbol.find(
{
$or: [
{ 'symbol': { '$regex': input, '$options': 'i' } },
{ 'name': { '$regex': input, '$options': 'i' } }
]
}
).then((data) => {
console.log(data)
}).catch((err) => {
console.log(err)
})
Here you are basing your search on if the input is contained in the symbol attribute or the name attribute.

Answer 12

If the regex is not working in your Aggregate solution and you have nested object. Try this aggregation pipeline: (If your object structure is simple then, just remove the other conditions from below query):
db.user.aggregate({$match:
{$and:[
{"UserObject.Personal.Status":"ACTV"},
{"UserObject.Personal.Address.Home.Type":"HME"},
{"UserObject.Personal.Address.Home.Value": /.*son.*/ }
]}}
)
One other way would be to directly query like this:
db.user.findOne({"UserObject.Personal.Address.Home.Value": /.*son.*/ });

Answer 13

If your regex includes a variable, make sure to escape it.
function escapeRegExp(string) {
return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
}
This can be used like this
new RegExp(escapeRegExp(searchString), 'i')
Or in a mongoDb query like this
{ '$regex': escapeRegExp(searchString) }
Posted same comment here

Answer 14

For aggregation framework
Field search
('$options': 'i' for case insensitive search)
db.users.aggregate([
{
$match: {
'email': { '$regex': '#gmail.com', '$options': 'i' }
}
}
]);
Full document search
(only works on fields indexed with a text index
db.articles.aggregate([
{
$match: { $text: { $search: 'brave new world' } }
}
])

Answer 15

How to ignore HTML tags in a RegExp match:
var text = '<p>The <b>tiger</b> (<i>Panthera tigris</i>) is the largest cat species, most recognizable for its pattern of dark vertical stripes on reddish-orange fur with a lighter underside. The species is classified in the genus <i>Panthera</i> with the lion, leopard, jaguar, and snow leopard. It is an apex predator, primarily preying on ungulates such as deer and bovids.</p>';
var searchString = 'largest cat species';
var rx = '';
searchString.split(' ').forEach(e => {
rx += '('+e+')((?:\\s*(?:<\/?\\w[^<>]*>)?\\s*)*)';
});
rx = new RegExp(rx, 'igm');
console.log(text.match(rx));
This is probably very easy to turn into a MongoDB aggregation filter.