# Creating a Query

When a user requests data using `tipQuery` or when a reporter submits data using `submitValue`, they have to input both the `queryId` and `queryData`. The `queryData` tells reporters how to fulfill the data query, while also informing voters how to verify the data in a dispute. The `queryId` is defined as the keccak256 hash of the `queryData` field.

In order to query the Tellor oracle you'll need to first generate the `queryData` and its hash, the `queryId`. 

### Getting a Query ID and Query Data

Use the tools below to generate a `queryId` and `queryData:`

{% embed url="<https://queryidbuilder.herokuapp.com/spotprice>" %}

{% embed url="<https://www.youtube.com/watch?index=2&list=PLuJHbmh0kCXVPHDA2Q3J3TfatBRGrOsm-&v=thjXi7FGLpU>" %}

{% hint style="info" %}
If the [existing Query Types](https://github.com/tellor-io/dataSpecs/tree/main/types) don't fit your needs you'll need to define a new one.
{% endhint %}

## Creating a new Query Type

To create a new Query Type, or specification, for custom data you need from Tellor oracles, there's two options:

* Make an issue like [this](https://github.com/tellor-io/dataSpecs/issues/25) and the Tellor team will help with the next steps.
* Fork this repository and make a pull request for a new Query type in `./types` using [this template](https://github.com/tellor-io/dataSpecs/blob/main/types/_NewQueryTypeTemplate.md).

To add a new data type to Tellor, you'll just need to define a new [queryType](https://github.com/tellor-io/dataSpecs) . This is how you form a question so that Tellor reporters know exactly what data is being requested. You'll need to determine three things: a unique queryType *name*, *inputs*, and *outputs*. So let's say you want a query for getting the price of any asset in any currency. In human-readable form, your question could look like this:

*What is the price of `asset` in `currency` ?*

You might formally define your query like this:

**Name**: `SpotPrice`

**Inputs**:

1\. *asset* (string): Asset ID (e.g. btc)

2\. *currency* (string): Selected currency (e.g. usd)

**Outputs**:

1\. *price* (uint256)

\- `abi_type`: ufixed256x18 (18 decimals of precision)

\- `packed`: false

Once Tellor reporters are submitting your new queryType on chain, you can retrieve your desired data with the help of [UsingTellor](https://github.com/tellor-io/usingtellor), which is a helper contract that provides various Tellor data getters. You'll first put your question in `queryData` format, which means encoding your queryType name and arguments into bytes (see below). You'll then need to get a `queryId`, which is the bytes32 unique identifier for each Tellor data feed. The `queryId` is defined as the keccak256 hash of `queryData`. Once you know the `queryId` you'll be able to retrieve your data.

In Solidity, your contract can get data like this:

```solidity
contract ExampleContract is UsingTellor {

    // _tellorAddress is the address of the Tellor oracle
    constructor(address payable _tellorAddress) UsingTellor(_tellorAddress) {}

    function getSpotPrice(string memory _asset, string memory _currency) external view returns(uint256) {
      bytes memory _queryData = abi.encode("SpotPrice", abi.encode(_asset, _currency));
      bytes32 _queryId = keccak256(_queryData);
      bool _ifRetrieve, bytes memory _value, uint256 _timestampRetrieved) = getDataBefore(_queryId, block.timestamp - 2 hours);
      if (!ifRetrieve) return 0;
      return abi.decode(_value, (uint256));
    }
}
```

### Example QueryData and QueryID

If you input `btc` and `usd`, respectively, the `queryData` would be:

> `0x00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000953706f745072696365000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000003627463000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000037573640000000000000000000000000000000000000000000000000000000000`

and the `queryId` would be

> `0xa6f013ee236804827b77696d350e9f0ac3e879328f2a3021d473a0b778ad78ac`

{% hint style="success" %}
Feel free to start building a query now and integrating it into your project. When you reach the later stages of building your project, add an issue to Tellor's [dataSpecs](https://github.com/tellor-io/dataSpecs/issues) repository so that data reporters know how to fulfill your query. Feel free to reach out to the Tellor team for assistance, and happy building!
{% endhint %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.tellor.io/tellor-docs-v2/getting-data/creating-a-query.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.