> For the complete MongoDB documentation index, see www.mongodb.com/docs/llms.txt

# dropIndexes (database command)

## Definition

**Changed in version 6.0**

The [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) command drops one or more indexes (except the index on the `_id` field and the last remaining shard key index, if one exists) from the specified collection.

**Tip:**

In [`mongosh`](https://www.mongodb.com/docs/mongodb-shell.md#std-program-mongosh), this command can also be run through the [`db.collection.dropIndex()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindex.md#mongodb-method-db.collection.dropIndex) and
[`db.collection.dropIndexes()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindexes.md#mongodb-method-db.collection.dropIndexes) helper methods..

Helper methods are convenient for [`mongosh`](https://www.mongodb.com/docs/mongodb-shell.md#std-program-mongosh) users, but they may not return the same level of information as database commands.  In cases where the convenience is not needed or the additional return fields are required, use the database command.

## Compatibility

This command is available in deployments hosted in the following environments:

- [MongoDB Atlas](https://www.mongodb.com/docs/atlas): The fully managed service for MongoDB deployments in the cloud

**Note:**

This command is supported in all MongoDB Atlas clusters. For information on Atlas support for all commands, see [Unsupported Commands.](https://www.mongodb.com/docs/atlas/unsupported-commands/)

- [MongoDB Enterprise](https://www.mongodb.com/docs/manual/administration/install-enterprise.md#std-label-install-mdb-enterprise): The subscription-based, self-managed version of MongoDB

- [MongoDB Community](https://www.mongodb.com/docs/manual/administration/install-community.md#std-label-install-mdb-community-edition): The source-available, free-to-use, and self-managed version of MongoDB

## Syntax

The command has the following syntax:

```javascript
db.runCommand(
   {
     dropIndexes: <string>,
     index: <string|document|arrayofstrings>,
     writeConcern: <document>, comment: <any>
   }
)
```

## Command Fields

The command takes the following fields:

| Field | Type | Description |
| --- | --- | --- |
| dropIndexes | String | The name of the collection whose indexes to drop. |
| index | string or document or array of strings | The index or indexes to drop. To drop all indexes except the `_id` index and the last remaining shard key index from the collection if one exists, specify `"*"`.; To drop a single index, specify either the index name, the index specification document (unless the index is a [text](https://www.mongodb.com/docs/manual/core/indexes/index-types/index-text.md#std-label-index-type-text) index), or an array of the index name. To drop a [text](https://www.mongodb.com/docs/manual/core/indexes/index-types/index-text.md#std-label-index-type-text) index, specify the index names instead of the index specification document. If this index is the last remaining shard key index, `dropIndexes` raises an error.; To drop multiple indexes, specify an array of the index names. |
| writeConcern | document | Optional. A document expressing the [write concern](https://www.mongodb.com/docs/manual/reference/write-concern.md) of the [`drop`](https://www.mongodb.com/docs/manual/reference/command/drop.md#mongodb-dbcommand-dbcmd.drop) command. Omit to use the default write concern. |
| `comment` | any | Optional. A user-provided comment to attach to this command. Once set, this comment appears alongside records of this command in the following locations: [mongod log messages](https://www.mongodb.com/docs/manual/reference/log-messages.md#std-label-log-messages-ref), in the `attr.command.cursor.comment` field.; [Database profiler](https://www.mongodb.com/docs/manual/reference/database-profiler.md#std-label-profiler) output, in the [`command.comment`](https://www.mongodb.com/docs/manual/reference/database-profiler.md#mongodb-data-system.profile.command) field.; [`currentOp`](https://www.mongodb.com/docs/manual/reference/command/currentop.md#mongodb-dbcommand-dbcmd.currentOp) output, in the [`command.comment`](https://www.mongodb.com/docs/manual/reference/command/currentop.md#mongodb-data-currentOp.command) field. A comment can be any valid [BSON type](https://www.mongodb.com/docs/manual/reference/bson-types.md#std-label-bson-types) (string, integer, object, array, etc). |

## Behavior

Starting in MongoDB 8.3, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) is idempotent. If you specify an index that does not exist, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) ignores the non-existent index and completes successfully instead of returning an `IndexNotFound` error. In earlier versions, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) returns an `IndexNotFound` error if the specified index does not exist.

Starting in MongoDB 6.0, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) raises an error if you attempt to use it to remove the last remaining shard key compatible index. Passing `"*"` to [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) drops all indexes except the `_id` index and the last remaining shard key compatible index, if one exists.

You can use [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) to drop existing indexes on the same collection even if there is a build in progress on another index. In earlier versions, attempting to drop a different index during an in-progress index build results in a `BackgroundOperationInProgressForNamespace` error.

### Kill related queries only

The [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) operation only kills queries that are using the index being dropped. This may include queries considering the index as part of [query planning.](https://www.mongodb.com/docs/manual/core/query-plans.md#std-label-query-plans-query-optimization)

### Resource Locking

[`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) obtains an exclusive lock on the specified collection for the duration of the operation. All subsequent operations on the collection must wait until [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) releases the lock.

### Index Names

Starting in MongoDB 8.3, if an array of index names includes a non-existent index, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) ignores the non-existent index and drops the remaining specified indexes.

### `_id` Index

You cannot drop the default index on the `_id` field.

### text Indexes

To drop a [text](https://www.mongodb.com/docs/manual/core/indexes/index-types/index-text.md#std-label-index-type-text) index, specify the index name instead of the index specification document.

### Stop In-Progress Index Builds

If an index specified to [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) is still building, [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) attempts to stop the in-progress build. Stopping an index build has the same effect as dropping the built index.

For replica sets, run [`dropIndexes`](https://www.mongodb.com/docs/manual/reference/command/dropindexes.md#mongodb-dbcommand-dbcmd.dropIndexes) on the [primary](https://www.mongodb.com/docs/manual/reference/glossary.md#std-term-primary). The primary stops the index build and creates an associated "abortIndexBuild" [oplog](https://www.mongodb.com/docs/manual/reference/glossary.md#std-term-oplog) entry. Secondaries which replicate the "abortIndexBuild" oplog entry stop the in-progress index build and discard the build job. See [Index Build Process](https://www.mongodb.com/docs/manual/core/index-creation.md#std-label-index-build-process) for detailed documentation on the index build process.

Use [`currentOp`](https://www.mongodb.com/docs/manual/reference/command/currentop.md#mongodb-dbcommand-dbcmd.currentOp) to identify the index builds associated with a [`createIndexes`](https://www.mongodb.com/docs/manual/reference/command/createindexes.md#mongodb-dbcommand-dbcmd.createIndexes) or [`db.collection.createIndexes()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.createindexes.md#mongodb-method-db.collection.createIndexes) operation. See [Active Indexing Operations](https://www.mongodb.com/docs/manual/reference/command/currentop.md#std-label-currentOp-cmd-index-creation) for an example.

### Hidden Indexes

MongoDB offers the ability to hide or unhide indexes from the query planner. By hiding an index from the planner, you can evaluate the potential impact of dropping an index without actually dropping the index.

If after the evaluation, the user decides to drop the index, you can drop the hidden index; i.e. you do not need to unhide it first to drop it.

If, however, the impact is negative, the user can unhide the index instead of having to recreate a dropped index. And because indexes are fully maintained while hidden, the indexes are immediately available for use once unhidden.

For more information on hidden indexes, see [Hidden Indexes.](https://www.mongodb.com/docs/manual/core/index-hidden.md)

## Examples

- To drop all non-`_id` indexes , specify `"*"` for the `index`.

  ```javascript
  db.runCommand( { dropIndexes: "collection", index: "*" } )
  ```

- To drop a single index, issue the command by specifying the name of the index you want to drop. For example, to drop the index named `age_1`, use the following command:

  ```javascript
  db.runCommand( { dropIndexes: "collection", index: "age_1" })
  ```

  [`mongosh`](https://www.mongodb.com/docs/mongodb-shell.md#mongodb-binary-bin.mongosh) provides the helper methods [`db.collection.dropIndex()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindex.md#mongodb-method-db.collection.dropIndex) and [`db.collection.dropIndexes()`:](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindexes.md#mongodb-method-db.collection.dropIndexes)

  ```javascript
  db.collection.dropIndex("age_1");
  ```

- To drop multiple indexes, issue the command by specifying an array of the index names:

  ```javascript
  db.runCommand( { dropIndexes: "collection", index: [ "age_1", "age_1_status_1" ] } )
  ```

**See also:**

- [`db.collection.dropIndexes()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindexes.md#mongodb-method-db.collection.dropIndexes)

- [`db.collection.dropIndex()`](https://www.mongodb.com/docs/manual/reference/method/db.collection.dropindex.md#mongodb-method-db.collection.dropIndex)