<commit_before>+++
date = "2015-03-19T12:53:35-04:00"
title = "Upgrade Guide"
[menu.main]
  identifier = "Upgrade Guide"
  weight = 45
  pre = "<i class='fa fa-cog'></i>"
+++

# What's new in 3.1

- Support for MongoDB version 4.0
- Support for Transactions
- Support for authentication with SCRAM-SHA-256
- Support for new URL parser (opt in with `useNewUrlParser` option for `MongoClient`)

[Full 3.1 Changes Here](https://github.com/mongodb/node-mongodb-native/blob/3.1/HISTORY.md#310-2018-06-27)

# What's new in 3.0

- Support added for Retryable Writes
- Support added for DNS Seedlists
- Support added for Change Streams<commit_msg>docs(changes): add Whats new in 3.2 to upgrade guide<commit_after>+++
date = "2015-03-19T12:53:35-04:00"
title = "Upgrade Guide"
[menu.main]
  identifier = "Upgrade Guide"
  weight = 45
  pre = "<i class='fa fa-cog'></i>"
+++

# What's new in 3.2

- Supports new "Unified Topology" for resolving servers (opt in with `useUnifiedTopology` option for `MongoClient`)
- Supports `session.withTransaction` helper
- Supports Asynchronous Iteration (`for await...` syntax) on cursors
- Supports Database-level Aggregations (`db.aggregate(pipeline, options)`)

[Full 3.2 Changes Here](https://github.com/mongodb/node-mongodb-native/releases/tag/v3.2.1)

# What's new in 3.1

- Support for MongoDB version 4.0
- Support for Transactions
- Support for authentication with SCRAM-SHA-256
- Support for new URL parser (opt in with `useNewUrlParser` option for `MongoClient`)

[Full 3.1 Changes Here](https://github.com/mongodb/node-mongodb-native/blob/3.1/HISTORY.md#310-2018-06-27)

# What's new in 3.0

- Support added for Retryable Writes
- Support added for DNS Seedlists
- Support added for Change Streams
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