How can I use 'Not Like' operator in MongoDB
RegexMongodbMongodb QueryPymongoSql LikeRegex Problem Overview
I can use the SQL Like
Operator using pymongo
,
db.test.find({'c':{'$regex':'ttt'}})
But how can I use Not Like
Operator?
I tried
db.test.find({'c':{'$not':{'$regex':'ttt'}})
but got error:
> OperationFailure: $not cannot have a regex
Regex Solutions
Solution 1 - Regex
From the docs:
> The $not operator does not support operations with the $regex > operator. Instead use // or in your driver interfaces, use your > language’s regular expression capability to create regular expression > objects. Consider the following example which uses the pattern match > expression //:
db.inventory.find( { item: { $not: /^p.*/ } } )
EDIT (@idbentley):
{$regex: 'ttt'}
is generally equivalent to /ttt/
in mongodb, so your query would become:
db.test.find({c: {$not: /ttt/}}
EDIT2 (@KyungHoon Kim):
In python, below one works:
'c':{'$not':re.compile('ttt')}
Solution 2 - Regex
You can do with regex which does not contain a word. Also, you can use $options => i
for case of insensitive search.
Doesn't Contain string
db.collection.find({name:{'$regex' : '^((?!string).)*$', '$options' : 'i'}})
Exact case insensitive string
db.collection.find({name:{'$regex' : '^string$', '$options' : 'i'}})
Starts with string
db.collection.find({name:{'$regex' : '^string', '$options' : 'i'}})
Ends with string
db.collection.find({name:{'$regex' : 'string$', '$options' : 'i'}})
Contains string
db.collection.find({name:{'$regex' : 'string', '$options' : 'i'}})
Keep this as a bookmark, and a reference for any other alterations you may need. http://www.cheatography.com/davechild/cheat-sheets/regular-expressions/