MongoDB is a highly popular open-source NoSQL database. It is acknowledged for its scalability and flexibility. It faces errors from time to time. The E11000 error is one of them. This error is often known as MongoError: E11000 Duplicate Key Error Collection. It is a server side error. You need to fix MongoDB server error E11000 if you regularly work with MongoDB. Here are some effective methods for your assistance:
Understand the Error E11000
The Mongo error with the code E11000 indicates the violation in its uniqueness, mainly in its collection. It interrupts documents from having duplicate keys/values. You face this server error when you try to update or insert a document that could violate its unique constraint. Your operation will be worthless.
Find the Cause
Step 1: After knowing the issue, comprehend why this error occurs. Usually, MongoDB produces an error message that has information on the duplicate key violation.
Step 2: Look for the field and value that is causing the conflict.
Step 3: Be very careful while finding the cause. It will facilitate you to fix MongoDB error E11000.
Check for Duplicate Values or Keys
Step 1: Check the database to find the existing duplicate keys or values.
Step 2: Use a GUI tool or the MongoDB shell to examine the collection in question.
Step 3: Identify and remove the duplicate values/keys. It will help you instantly resolve the issue.
Update the Current Documents
Step 1: Make it sure that the existing document has no values causing the conflict if you face the error during an update operation.
Step 2: Modify the document if you notice a value/key behind the problem.
Step 3: Keep the unique index constraint in mind.
Remove the Unique Index
Step 1: Consider removing the unique index constraint if you think it is not useful for your use case.
Step 2: Be careful during the index removal and think whether it would affect the integrity of your application.
Step 3: Use the db.collection.dropindex() process in the MongoDB shell. It will remove the unique index or duplicacy.
Handle Constraint in the Application Code
Step 1: Use the application code to handle the issue.
Step 2: Check whether the value is already in the collection before you move to perform an update or insert operation.
Step 3: Notify the user about the issue or update the existing documents if the collection has a value.
Retry the Operation
Step 1: Wait for a while if you think the issue is a race condition or temporary problem.
Step 2: After a short break, see whether the issue persists.
Step 3: Apply backoff strategies to retry the operation.
Upsert Operations
Step 1: Think about using upsert operations to optimize the process. The upsert process is a combination of update and insert operations.
Step 2: Try to insert a document as you see a key violation.
Step 3: Or update the existing document. It will lower your chances of having this server error code.
