Is there a length limit to field values in mongo queries?

mongodb

Solution

The limit you are encountering is the maximum line buffer size in the `mongo` shell, which is 4096 bytes as at MongoDB 2.2.1. If you try pasting your example in the `mongo` shell you should notice that you cannot add any characters beyond the line limit.

If you execute this query from a language driver you will not have this issue.

You could also workaround this in the `mongo` shell by loading the query from a JavaScript file specified on the command line:

 mongo longname.js

Or by creating a long string in the `mongo` shell programmatically:

// Longname will be 5000 characters
var longname = '';
for (i = 0; i < 200; i++) {
    longname += 'Abcdefghijklmnopqrstuvwx ';
}

db.foo.insert({
  _id: ObjectId("508836afea5cea2ccec11a0d"),
  created_at: 1348657869.204,
  name: longname
});

printjson(db.foo.findOne({name: longname}))

Problem

I've got a single document in a collection: ``` { _id: ObjectId("508836afea5cea2ccec11a0d"), created_at: 1348657869.204, name: "Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx Abcdefghijklmnopqrstuvwx 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Is there a length limit to the field in the query?

Original source