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# Set Primary Keys

PUT https://app.polytomic.com/api/connections/{connection_id}/schemas/{schema_id}/primary_keys
Content-Type: application/json

Overrides the primary key detected on a schema.

This is a full replacement: the keys you supply become the complete override
set, replacing any previously configured overrides. Omitting a key that was
previously set removes it.

Primary key overrides are useful when the source does not expose a primary
key or when the source-detected key is not the correct deduplication
identifier for your use case.

> 📘 To revert to the source-detected primary keys and remove all overrides,
> use [`DELETE /api/connections/{connection_id}/schemas/{schema_id}/primary_keys`](../../../../../../api-reference/schemas/reset-primary-keys).

Reference: https://apidocs.polytomic.com/api-reference/schemas/set-primary-keys

## Authentication

- `Authorization` header (bearer token, required) — Bearer user API key
- `Authorization` header (basic auth, required) — Basic organization-scoped API key

## Request

### Path parameters

- `connection_id` (string, required) — Unique identifier of the connection.
- `schema_id` (string, required) — Identifier of the schema whose primary keys are being overridden.

### Body (application/json)

This endpoint expects a SetPrimaryKeysRequest.

- `fields` (list of SchemaPrimaryKeyOverrideInput, optional, nullable) — Ordered list of source fields that together form the primary key. Replaces any existing override; supply an empty list to clear.

## Response

### 202

Accepted

## Errors

### 400 Bad Request Error

Bad Request

- `key` (string, optional)
- `message` (string, optional)
- `metadata` (map from string to any, optional)
- `status` (integer, optional)

### 404 Not Found Error

Not Found

- `key` (string, optional)
- `message` (string, optional)
- `metadata` (map from string to any, optional)
- `status` (integer, optional)

### 500 Internal Server Error

Internal Server Error

- `key` (string, optional)
- `message` (string, optional)
- `metadata` (map from string to any, optional)
- `status` (integer, optional)

## Types

### SchemaPrimaryKeyOverrideInput

- `field_id` (string, required)
- `is_primary_key` (boolean, required)

## Examples

**Request**

```json
{}
```

**Response**

```json
{}
```

**SDK Code**

```python
import requests

url = "https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys"

payload = {}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.put(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys';
const options = {
  method: 'PUT',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys"

	payload := strings.NewReader("{}")

	req, _ := http.NewRequest("PUT", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Put.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{}"

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.put("https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('PUT', 'https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys', [
  'body' => '{}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys");
var request = new RestRequest(Method.PUT);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = [] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://app.polytomic.com/api/connections/248df4b7-aa70-47b8-a036-33ac447e668d/schemas/public.users/primary_keys")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "PUT"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```