debian-mirror-gitlab/doc/user/project/merge_requests/getting_started.md

---
stage: Create
group: Code Review
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
type: index, reference
description: "Getting started with merge requests."
---

# Getting started with merge requests **(FREE)**

A merge request (**MR**) is the basis of GitLab as a code
collaboration and version control.

When working in a Git-based platform, you can use branching
strategies to collaborate on code.

A repository is composed by its _default branch_, which contains
the major version of the codebase, from which you create minor
branches, also called _feature branches_, to propose changes to
the codebase without introducing them directly into the major
version of the codebase.

Branching is especially important when collaborating with others,
avoiding changes to be pushed directly to the default branch
without prior reviews, tests, and approvals.

When you create a new feature branch, change the files, and push
it to GitLab, you have the option to create a **merge request**,
which is essentially a _request_ to merge one branch into another.

The branch you added your changes into is called _source branch_
while the branch you request to merge your changes into is
called _target branch_.

The target branch can be the default or any other branch, depending
on the branching strategies you choose.

In a merge request, beyond visualizing the differences between the
original content and your proposed changes, you can execute a
[significant number of tasks](#what-you-can-do-with-merge-requests)
before concluding your work and merging the merge request.

You can watch our [GitLab Flow video](https://www.youtube.com/watch?v=InKNIvky2KE) for
a quick overview of working with merge requests.

## How to create a merge request

Learn the various ways to [create a merge request](creating_merge_requests.md).

## What you can do with merge requests

When you start a new merge request, you can immediately include the following
options, or add them later by clicking the **Edit** button on the merge
request's page at the top-right side:

- [Assign](#assignee) the merge request to a colleague for review. With [multiple assignees](#multiple-assignees), you can assign it to more than one person at a time.
- Set a [milestone](../milestones/index.md) to track time-sensitive changes.
- Add [labels](../labels.md) to help contextualize and filter your merge requests over time.
- [Require approval](approvals/index.md#required-approvals) from your team. **(PREMIUM)**
- [Close issues automatically](#merge-requests-to-close-issues) when they are merged.
- Enable the [delete source branch when merge request is accepted](#deleting-the-source-branch) option to keep your repository clean.
- Enable the [squash commits when merge request is accepted](squash_and_merge.md) option to combine all the commits into one before merging, thus keep a clean commit history in your repository.
- Set the merge request as a [**Draft**](drafts.md) to avoid accidental merges before it is ready.

After you have created the merge request, you can also:

- [Discuss](../../discussions/index.md) your implementation with your team in the merge request thread.
- [Perform inline code reviews](reviews/index.md#perform-inline-code-reviews).
- Add [merge request dependencies](merge_request_dependencies.md) to restrict it to be merged only when other merge requests have been merged. **(PREMIUM)**
- Preview continuous integration [pipelines on the merge request widget](reviews/index.md#pipeline-status-in-merge-requests-widgets).
- Preview how your changes look directly on your deployed application with [Review Apps](reviews/index.md#live-preview-with-review-apps).
- [Allow collaboration on merge requests across forks](allow_collaboration.md).
- Perform a [Review](reviews/index.md) to create multiple comments on a diff and publish them when you're ready.
- Add [code suggestions](reviews/suggestions.md) to change the content of merge requests directly into merge request threads, and easily apply them to the codebase directly from the UI.
- Add a time estimation and the time spent with that merge request with [Time Tracking](../time_tracking.md#time-tracking).

Many of these can be set when pushing changes from the command line,
with [Git push options](../push_options.md).

See also other [features associated to merge requests](reviews/index.md#associated-features).

### Assignee

Choose an assignee to designate someone as the person responsible
for the first [review of the merge request](reviews/index.md).
Open the drop down box to search for the user you wish to assign,
and the merge request is added to their
[assigned merge request list](../../search/index.md#issues-and-merge-requests).

#### Multiple assignees **(PREMIUM)**

> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/2004) in GitLab 11.11.
> - Moved to GitLab Premium in 13.9

Multiple people often review merge requests at the same time.
GitLab allows you to have multiple assignees for merge requests
to indicate everyone that is reviewing or accountable for it.

![multiple assignees for merge requests sidebar](img/multiple_assignees_for_merge_requests_sidebar.png)

To assign multiple assignees to a merge request:

1. From a merge request, expand the right sidebar and locate the **Assignees** section.
1. Click on **Edit** and from the dropdown menu, select as many users as you want
   to assign the merge request to.

Similarly, assignees are removed by deselecting them from the same
dropdown menu.

It is also possible to manage multiple assignees:

- When creating a merge request.
- Using [quick actions](../quick_actions.md#issues-merge-requests-and-epics).

### Reviewer

> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/216054) in GitLab 13.5.
> - [Feature flag removed](https://gitlab.com/gitlab-org/gitlab/-/issues/245190) in GitLab 13.9.

WARNING:
Requesting a code review is an important part of contributing code. However, deciding who should review
your code and asking for a review are no easy tasks. Using the "assignee" field for both authors and
reviewers makes it hard for others to determine who's doing what on a merge request.

The merge request Reviewers feature enables you to request a review of your work, and
see the status of the review. Reviewers help distinguish the roles of the users
involved in the merge request. In comparison to an **Assignee**, who is directly
responsible for creating or merging a merge request, a **Reviewer** is a team member
who may only be involved in one aspect of the merge request, such as a peer review.

To request a review of a merge request, expand the **Reviewers** select box in
the right-hand sidebar. Search for the users you want to request a review from.
When selected, GitLab creates a [to-do list item](../../todos.md) for each reviewer.

#### Approval Rule information for Reviewers **(PREMIUM)**

> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/233736) in GitLab 13.8.
> - [Feature flag removed](https://gitlab.com/gitlab-org/gitlab/-/issues/293742) in GitLab 13.9.

When editing the **Reviewers** field in a new or existing merge request, GitLab
displays the name of the matching [approval rule](approvals/rules.md)
below the name of each suggested reviewer. [Code Owners](../code_owners.md) are displayed as `Codeowner` without group detail.

This example shows reviewers and approval rules when creating a new merge request:

![Reviewer approval rules in new/edit form](img/reviewer_approval_rules_form_v13_8.png)

This example shows reviewers and approval rules in a merge request sidebar:

![Reviewer approval rules in sidebar](img/reviewer_approval_rules_sidebar_v13_8.png)

#### Requesting a new review

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/293933) in GitLab 13.9.

After a reviewer completes their [merge request reviews](../../discussions/index.md),
the author of the merge request can request a new review from the reviewer:

1. If the right sidebar in the merge request is collapsed, click the
   **{chevron-double-lg-left}** **Expand Sidebar** icon to expand it.
1. In the **Reviewers** section, click the **Re-request a review** icon (**{redo}**)
   next to the reviewer's name.

GitLab creates a new [to-do item](../../todos.md) for the reviewer, and sends
them a notification email.

#### Approval status

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/292936) in GitLab 13.10.

If a user in the reviewer list has approved the merge request, a green tick symbol is
shown to the right of their name.

### Merge requests to close issues

If the merge request is being created to resolve an issue, you can
add a note in the description which sets it to
[automatically close the issue](../issues/managing_issues.md#closing-issues-automatically)
when merged.

If the issue is [confidential](../issues/confidential_issues.md),
you may want to use a different workflow for
[merge requests for confidential issues](../issues/confidential_issues.md#merge-requests-for-confidential-issues)
to prevent confidential information from being exposed.

### Deleting the source branch

When creating a merge request, select the
**Delete source branch when merge request accepted** option, and the source
branch is deleted when the merge request is merged. To make this option
enabled by default for all new merge requests, enable it in the
[project's settings](../settings/index.md#merge-request-settings).

This option is also visible in an existing merge request next to
the merge request button and can be selected or deselected before merging.
It is only visible to users with [Maintainer permissions](../../permissions.md)
in the source project.

If the user viewing the merge request does not have the correct
permissions to delete the source branch and the source branch
is set for deletion, the merge request widget displays the
**Deletes source branch** text.

![Delete source branch status](img/remove_source_branch_status.png)

### Branch retargeting on merge **(FREE SELF)**

> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/320902) in GitLab 13.9.
> - [Deployed behind a feature flag](../../feature_flags.md), disabled by default.
> - [Enabled by default](https://gitlab.com/gitlab-org/gitlab/-/issues/320895) in GitLab 13.10.
> - Recommended for production use.
> - To use in GitLab self-managed instances, ask a GitLab administrator to [disable it](#enable-or-disable-branch-retargeting-on-merge). **(FREE SELF)**

In specific circumstances, GitLab can retarget the destination branch of
open merge request, if the destination branch merges while the merge request is
open. Merge requests are often chained in this manner, with one merge request
depending on another:

- **Merge request 1**: merge `feature-alpha` into `master`.
- **Merge request 2**: merge `feature-beta` into `feature-alpha`.

These merge requests are usually handled in one of these ways:

- Merge request 1 is merged into `master` first. Merge request 2 is then
  retargeted to `master`.
- Merge request 2 is merged into `feature-alpha`. The updated merge request 1, which
  now contains the contents of `feature-alpha` and `feature-beta`, is merged into `master`.

GitLab retargets up to four merge requests when their target branch is merged into
`master`, so you don't need to perform this operation manually. Merge requests from
forks are not retargeted.

The feature today works only on merge. Clicking the **Remove source branch** button
after the merge request was merged will not automatically retarget a merge request.
This improvement is [tracked as a follow-up](https://gitlab.com/gitlab-org/gitlab/-/issues/321559).

## Recommendations and best practices for merge requests

- When working locally in your branch, add multiple commits and only push when
  you're done, so GitLab runs only one pipeline for all the commits pushed
  at once. By doing so, you save pipeline minutes.
- Delete feature branches on merge or after merging them to keep your repository clean.
- Take one thing at a time and ship the smallest changes possible. By doing so,
  reviews are faster and your changes are less prone to errors.
- Do not use capital letters nor special chars in branch names.

### Enable or disable branch retargeting on merge **(FREE SELF)**

Automatically retargeting merge requests is under development but ready for production use.
It is deployed behind a feature flag that is **enabled by default**.
[GitLab administrators with access to the GitLab Rails console](../../../administration/feature_flags.md)
can opt to disable it.

To enable it:

```ruby
Feature.enable(:retarget_merge_requests)
```

To disable it:

```ruby
Feature.disable(:retarget_merge_requests)
```