How do I fix a duplicate key in MongoDB?
You essentially have three options:
- Drop the collection. db.users.drop();
- Find the document which has that value and delete it. Let’s say the value was null, you can delete it using: db.users.remove({ email_address: null });
- Drop the Unique index: db.users.dropIndex(indexName)
What is duplicate error?
“The error message “Duplicate Transaction” indicates that a transaction request with the same information has been submitted within two minutes of a previous attempt. If duplicateWindow is set to 0 or to a negative number, no duplicate transaction window will be enforced for your software’s transactions.
What does Cannot INSERT duplicate key mean?
It just means that you are inserting a value that already exists on the table.
How do I upsert multiple documents in MongoDB?
In MongoDB, you can update multiple documents in the collection using db. collection. updateMany() method.
- updateMany() method can be used in the multi-document transactions.
- When you update your documents the value of _id field in not change.
- It also adds new fields in the documents.
Why is there duplicate key error in MongoDB?
The reason behind this error is that. The index is not present in your collection, in which you are trying insert the record. So Solution is – Drop that collection and run your program again.
How to get rid of duplicate Index in MongoDB?
Check with mydb.users.getIndexes () if this is the case and manually remove the unwanted index with mydb.users.dropIndex ( ). If you are still in your development environment, I would drop the entire db and start over with your new schema.
Why does unique indexing not work in MongoDB?
Unique Indexing (compound or not) will not work if there any record that violates the new desired indexing, even if you drop all your indexes and retry to reIndex as I mentioned before. The reason behind this error is that. The index is not present in your collection, in which you are trying insert the record.
Why is there an error message in MongoDB?
The error message is saying that there’s already a record with null as the email. In other words, you already have a user without an email address. If a document does not have a value for the indexed field in a unique index, the index will store a null value for this document.