---
id: upsert
title: "Upsert data: upsert()"
slug: upsert
custom_edit_url: https://github.com/supabase/supabase/edit/master/web/spec/dart.yml
---

import Tabs from '@theme/Tabs';
import TabsPanel from '@theme/TabsPanel';

Performs an UPSERT into the table.


<Tabs
  defaultActiveId="dart"
  groupId="reference/dart"
  values={[{ label: 'Dart', value: 'dart' }]}>

<TabsPanel id="dart" label="dart">

```dart
final res = await supabase
  .from('messages')
  .upsert({ 'id': 3, 'message': 'foo', 'username': 'supabot' })
  .execute();
```


</TabsPanel>

</Tabs>





## Notes

- Primary keys should be included in the data payload in order for an update to work correctly. 
- Primary keys must be natural, not surrogate. There are however, [workarounds](https://github.com/PostgREST/postgrest/issues/1118) for surrogate primary keys.










## Examples

### Upsert your data



<Tabs
  defaultActiveId="dart"
  groupId="reference/dart"
  values={[{ label: 'Dart', value: 'dart' }]}>

<TabsPanel id="dart" label="dart">

```dart
final res = await supabase
  .from('messages')
  .upsert({ 'id': 3, 'message': 'foo', 'username': 'supabot' })
  .execute();
```


</TabsPanel>

</Tabs>

### Upserting into tables with constraints

Running the following will cause supabase to upsert data into the `users` table. 
If the username 'supabot' already exists, the `onConflict` argument tells supabase to overwrite that row 
based on the column passed into `onConflict`.


<Tabs
  defaultActiveId="dart"
  groupId="reference/dart"
  values={[{ label: 'Dart', value: 'dart' }]}>

<TabsPanel id="dart" label="dart">

```dart
final res = await supabase
  .from('users')
  .upsert({ 'username': 'supabot' }, { 'onConflict': 'username' })
  .execute();
```


</TabsPanel>

</Tabs>

### Return the exact number of rows

Allowed values for count option are `exact`, `planned` and `estimated`.


<Tabs
  defaultActiveId="dart"
  groupId="reference/dart"
  values={[{ label: 'Dart', value: 'dart' }]}>

<TabsPanel id="dart" label="dart">

```dart
final res = await supabase
  .from('users')
  .upsert({ 
      'id': 3,
      'message': 'foo', 
      'username': 'supabot' 
  })
  .execute(count: CountOption.exact);
```


</TabsPanel>

</Tabs>