How to Find a Substring in a Field in Mongodb
How Can I Find All the Objects in a Database with Where a Field of a Object Contains a Substring? If the Field Is a in an Object of a Collection with a String...
How can I find all the objects in a database with where a field of a object contains a substring?
If the field is A in an object of a collection with a string value:
I want to find all the objects in the db "database" where A contains a substring say "abc def".
I tried:
db.database.find({A: {$regex: '/^*(abc def)*$/''}})
but didn't work
UPDATE
A real string (in unicode):
Sujet Commentaire sur Star Wars Episode III - La Revanche des Sith 1
Need to search for all entries with Star Wars
db.test.find({A: {$regex: '^*(star wars)*$''}}) not wokring
6 Answers
Instead of this:
db.database.find({A: {$regex: '/^*(abc def)*$/''}})
You should do this:
db.database.find({A: /abc def/i })
^* is not actually valid syntax as ^ and $ are anchors and not something that is repeatable. You probably meant ^.* here. But there is no need for ^.* as that simply means "Everything up to the character following" and (abc def)* means "0 or more times "abc def", but it has to be at the end of the string, because of your $. The "i" at the end is to make it case insensitive.
Just use the string "Star Wars" and $regex will do the rest
db.test.find({A: {$regex: 'Star Wars'}})
$regex is too expensive/slow on large collections.
I'd suggest to leverage aggregation framework and $indexOfCP.
db.test.aggregate([{$match:
{$expr: { $gt: [{ $indexOfCP: [ "$A", "Star Wars" ] }, -1]}}
}, {$project: {A:1}}])
For case-insensitive search you may add $toUpper to the mix and search for STAR WARS.
This worked for me:
db.test.find({"A": {'$regex': '.*star wars.*'}})
// executes, name LIKE john and only selecting the "name" and "friends" fields
db.collection.find({ name: /john/i }, 'name friends').exec();
// passing options
db.collection.find({ name: /john/i }, null, { skip: 10 }).exec();
this one uses the aggregation syntax:
db.movies.aggregate([
{$match:
{
title: {$regex: 'Star'}
}
}
] )
Sarah Jenkins is a veteran tech journalist with over 12 years of experience covering artificial intelligence, mobile innovations, and digital ethics. Her insights have appeared in leading technology publications worldwide.
