# Use the GraphQL Explorer and the SDK

On this page, we will look in more detail at sending GraphQL requests. We'll explore two options: one using the GraphQL Explorer in the Merchant Center, and the other using the SDK.

## GraphQL Explorer

The [GraphQL Explorer](/merchant-center/developer-settings.md#graphql-explorer) is a built-in IDE in the Merchant Center for running GraphQL queries and mutations against your Project. To access it, go to **Settings** > **Developer settings** and click the **GraphQL Explorer** tab.

The GraphQL Explorer provides a query editor with autocomplete, a results window, and a Documentation Explorer for browsing the schema. Additional features include query prettification and history. For a full walkthrough of the interface, see [GraphQL Explorer](/merchant-center/developer-settings.md#graphql-explorer) in the Merchant Center documentation.

## Use the SDKs

How can we begin to use GraphQL in our code? Just like our commercetools SDKs provide help in using the REST APIs, they also provide [help in using GraphQL](https://commercetools.github.io/commercetools-sdk-java-v2/javadoc/com/commercetools/docs/meta/GraphQL.html). For additional SDK examples, including TypeScript, Java, and .NET, see [Using an SDK](/api/graphql.md#using-an-sdk) in the GraphQL API reference.

See our examples below for creating the Customer query using `sort` and `where` parameters that we explored earlier.

```typescript
const query = `
query {
 customers(where: "firstName=\\"Martha\\"", sort: "id asc" ) {
   results {
     firstName
     lastName
     email
   }
 }
}
`;

async function customerFetch() {
  try {
    const response = await apiRoot
      .graphql()
      .post({ body: { query } })
      .execute();

    console.log('Success', JSON.stringify(response.body, null, 2));
  } catch (error) {
    console.log(JSON.stringify(error, null, 2));
  }
}

customerFetch();
```

The commercetools Java SDK has a module that provides GraphQL support. It generates a type-safe query and projection builder. Results can be mapped to the correct response type.

```java
GraphQLResponse<CustomerQueryResult> response = client
  .graphql()
  .query(
    GraphQL
      .customers(query ->
        query
          .sort((Collections.singletonList("id asc")))
          .where("firstName=\"Martha\"")
      )
      .projection(root -> root.results().firstName().lastName().email())
  )
  .executeBlocking()
  .getBody();

logger.info("Total Customers: " + response.getData().getTotal());
logger.info("First" + "\t" + "Last" + "\t" + "Email");
logger.info("-----" + "\t" + "----" + "\t" + "-----");
response
  .getData()
  .getResults()
  .forEach(result ->
    logger.info(
      result.getFirstName() +
      "\t" +
      result.getLastName() +
      "\t" +
      result.getEmail()
    )
  );
client.close();
```

Which outputs the following (modified to remove some logger info):

```json
{
  "data": {
    "customers": {
      "results": [
        {
          "firstName": "Martha",
          "lastName": "Jones",
          "email": "martha@example.uk"
        },
        {
          "firstName": "Martha",
          "lastName": "Schmidt",
          "email": "martha@example.de"
        },
        {
          "firstName": "Martha",
          "lastName": "Robinson",
          "email": "martha@example.com"
        }
      ]
    }
  }
}
```

## Related pages

- [Area overview page with navigation](/learning-developer-essentials.md)
- [Previous page: Develop with GraphQL](/learning-developer-essentials/graphql/develop-with-graphql.md)
- [Next page: Create a GraphQL query](/learning-developer-essentials/graphql/create-a-graphql-query.md)