How can I replace a substring with another in mongodb?

Question

I want to replace a substring "are" with "any test" in all "ques" document of "user" collection,but my query is replace the full document string with "any test".I am new to mongo. Please someone suggest me what wrong with my query?

Here is my mongo query.

db.user.find({ques:{$regex:'are'}}).forEach(function (e, i) {e.ques =  e.ques.replace(/are/, 'any test'), printjson(e); db.ques.save(e);} )

Does this answer your question? [How to replace substring in mongodb document](https://stackoverflow.com/questions/12589792/how-to-replace-substring-in-mongodb-document) — PZBird, Jan 18 '23 at 06:43
PZBird.this command db.faq.find().forEach(function(o) {o.ques = o.ques.replace(/hello/, "How"); printjson(o);db.faq.save(o)}) is okay in localhost but in server it show that "db.faq.save" is not a function — Ratnambar Gupta, Jan 18 '23 at 07:29

lpizzinidev · Answer 1 · 2023-01-18T07:52:28.597

1

Try with:

db.user.find({ ques: { $regex: 'are' } }).toArray((err, users) => {
    if (err) return;
    for (const u of users) {
        u.ques = u.ques.replace(/are/, 'any test');
        db.user.save(u);
    }
});

edited Jan 18 '23 at 07:52

answered Jan 18 '23 at 07:26

lpizzinidev

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Hii @lpizzinidev I found "MongoServerError: Expected field projectionto be of type object" error – Ratnambar Gupta Jan 18 '23 at 07:44
1

@RatnambarGupta Try with `toArray` (see edited answer) – lpizzinidev Jan 18 '23 at 07:54

How can I replace a substring with another in mongodb?

1 Answers1