mongodb exculde matched to the data?

Question

there are some data in mongodb:

{'name': 'bob', age: 12}
{'name': 'sam': age: 34}
{'name': 'byaelle': age: 22}

if I want to get the data of name include am
I can use

{'name': {'$regex': 'am'}}

But, how can I get the data of name exclude am?

score 7 · Accepted Answer · edited Jul 06 '15 at 20:43

7

Of course you can just reverse with $not:

db.collection.find({ "name": { "$not": /am/  } })

But since it's a $regex you can just do this:

db.collection.find({ "name": /^((?!am).)*$/ })

Or

db.collection.find({ "name": { "$regex": "^((?!am).)*$", "$options": "gm" } })

Making sure that the content matches over multiple lines if your string is formed that way.

For multiple fragments to exclude you can separate them in the expression using |. For example to exclude words containing "bo" or "am":

db.collection.find({ "name": { "$regex": "^((?!bo|am).)*$", "$options": "gm" } })

Or use the $nin operator ( "not" $in ) which accepts regular expressions:

db.collection.find({ "name": { "$nin": [/bo/,/am/] } })

edited Jul 06 '15 at 20:43

styvane

answered Jul 06 '15 at 03:31

Blakes Seven

if I want get name exclude `am` and `bo` and so on? – nataila Jul 06 '15 at 06:21
@nataila `^((?!bo|am).)*$` so use `|`. which sort of means "or". Get the idea? – Blakes Seven Jul 06 '15 at 06:25
if I want use `$not`? – nataila Jul 06 '15 at 07:02
@nataila Explained above. In the future, you only get to ask **one** question per question submitted here. You should be posting additional questions if you have more questions. – Blakes Seven Jul 06 '15 at 07:08

score 1 · Answer 2 · edited May 23 '17 at 11:51

1

You need to use the $not operator with a regular expression objects because $not cannot have a $regex

db.collection.find( { "name": { "$not" : /am/ }})

You can also use the following regex ^((?!am).)*$ to match text that doesn't contain a word.

collection.find({ 'name': { '$regex': '^((?!am).)*$' }})

edited May 23 '17 at 11:51

Community

answered Jul 06 '15 at 03:26

styvane

2 Answers2