Querying data with GraphQL

Using GraphQL

You can use the GraphQL protocol to query data from hyperfluid.

Just send a POST request to the data dock’s GraphQL endpoint with the correct query and you will get a result.

The next sections will show you how to query data from hyperfluid using GraphQL.

You can test the queries using the GraphQL playground.

Search for data

Querying a table

Let’s say you want to query the customer table from the sf100 schema in the tpch dataset. You will do as follows:

{
  tpch {
    sf100 {
      customer {
        name
        custkey
        nationkey
      }
    }
  }
}

For the sake of simplicity, we are only querying the fields name, custkey, and nationkey, but you can query any field you want. You can see every available field in the bifrost view of the data dock.

Limiting the number of results

Because the customer table has a lot of rows, you may want to limit the number of results. You can do this by adding the limit argument to the query.

{
  tpch {
    sf100 {
      customer(
        limit: 10
      ) {
        name
        custkey
        nationkey
      }
    }
  }
}

Filtering

You can also filter the results by adding the filters argument to the query. The filters argument is an object with the fields you want to filter and the operator you want to use.

The available operators are:

In the following example, we want the customers with the name “Customer#011250010”.

{
  tpch {
    sf100 {
      customer(
        filters: {
          name: "Customer#011250010"
          operator: EQ
        }
        limit: 10
      ) {
        name
        custkey
        nationkey
      }
    }
  }
}

And here is an example where we want any customers that are not from nationkey 11.

{
  tpch {
    sf100 {
      customer(
        filters: {
          nationkey: 11
          operator: NEQ
        }
        limit: 10
      ) {
        name
        custkey
        nationkey
      }
    }
  }
}

Combining filters

In some cases, you may want to combine filters. For example, you could want to have the customer Customer#011250010 and all customers coming from nationkey 11.

That is done by adding the or or and argument to the filters object and putting another filter inside it.

{
  tpch {
    sf100 {
      customer(
        filters: {
          name: "Customer#011250010"
          operator: EQ
          or: {
            nationkey: 11
            operator: EQ
          }
        }
        limit: 10
      ) {
        name
        custkey
        nationkey
      }
    }
  }
}

Those filters can be combined as much as you want. Here is an example with three filters, where we want the customer Customer#011250010, or the customer Customer#003750003 that is from nationkey 11.

{
  tpch {
    sf100 {
      customer(
        filters: {
          name: "Customer#011250010"
          operator: EQ
          or: {
            name: "Customer#003750003"
            operator: EQ
            and: { nationkey: 11, operator: EQ }
          }
        }
        limit: 10
      ) {
        name
        custkey
        nationkey
      }
    }
  }
}

Security

In order to query data from the data dock, you need to be authenticated. For that, you need to pass the Authorization header with the value Bearer <your-token> in the request headers. You can see how to obtain your access token here.