> For the complete documentation index, see [llms.txt](https://v2.dataos.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://v2.dataos.info/concepts/foundations/activation/apis/getting-started/querying-data-products.md).

# Querying Data Products

A data product exposes two ways to read data.

**Semantic models** are the governed layer. They define measures, dimensions, segments, and joins in a project. Queries use member names, such as `users.plan_type` or `store_revenue.measure`, not warehouse column names. REST, Semantic SQL, GraphQL, and the Metric API all target this layer. The request is transpiled into warehouse SQL, executed on the gateway, and returned as a statement result.

**Physical models** are the underlying warehouse tables. Source SQL runs a `SELECT` written directly against those tables. It does not use the transpiler or semantic member names. Use Source SQL for ad-hoc access or for columns the semantic layer does not expose.

Most interfaces return `202 Accepted` and a statement id. You poll until the query finishes, then fetch rows. GraphQL usually returns data in one response. Long queries fall back to the same poll-and-fetch flow.

<table><thead><tr><th width="132.6046142578125">Path</th><th width="345.84765625">Input</th><th>What runs</th></tr></thead><tbody><tr><td>Semantic</td><td>REST, GraphQL, Semantic SQL, or Metric API</td><td>Transpiler → warehouse SQL → gateway</td></tr><tr><td>Physical</td><td>Source SQL</td><td>The <code>SELECT</code> statement → gateway</td></tr></tbody></table>

Member names use `model.column`. Time buckets add a granularity suffix (`users.signup_date.month`).

Use these pages to choose the right interface and understand shared query behavior.

{% hint style="info" %}
Semantic interfaces target the same governed layer. Most of them use submit, poll, then fetch.
{% endhint %}

### Choose an interface

<table data-view="cards"><thead><tr><th>Title</th><th data-card-target data-type="content-ref">Target</th></tr></thead><tbody><tr><td><strong>REST</strong><br>Use JSON queries for precise programmatic control.</td><td><a href="/pages/dpV4c6mjQFAAiOm3Bn4k">/pages/dpV4c6mjQFAAiOm3Bn4k</a></td></tr><tr><td><strong>Semantic SQL</strong><br>Use SQL syntax on top of semantic models.</td><td><a href="/pages/rxjBV6xx2KWETvmpvRmr">/pages/rxjBV6xx2KWETvmpvRmr</a></td></tr><tr><td><strong>GraphQL</strong><br>Use typed field selection and schema introspection.</td><td><a href="/pages/3D0SbSW7ssLWgHFFONW2">/pages/3D0SbSW7ssLWgHFFONW2</a></td></tr><tr><td><strong>Metrics</strong><br>Use the shortest path for querying <code>METRIC</code> models.</td><td><a href="/pages/gLJLzsmjcSPHmEfzxMoc">/pages/gLJLzsmjcSPHmEfzxMoc</a></td></tr><tr><td><strong>Source SQL</strong><br>Use direct <code>SELECT</code> access to physical tables.</td><td><a href="/pages/5xQ1xlU7yiamdtObYWyz">/pages/5xQ1xlU7yiamdtObYWyz</a></td></tr></tbody></table>

### Quick guidance

{% columns %}
{% column %}

#### Use semantic interfaces when

* Governed measures and dimensions are required.
* Model-aware joins and segments are required.
* Queries need to use member names.
  {% endcolumn %}

{% column %}

#### Use Source SQL when

* Direct physical table access is required.
* Raw warehouse SQL control is required.
* The semantic layer does not expose a field.
  {% endcolumn %}
  {% endcolumns %}

### Shared reference

* [Statement lifecycle](/concepts/foundations/activation/apis/getting-started/querying-data-products/statement-lifecycle.md) — async execution, polling, results, and deduplication.
* [Measure and dimension behavior](/concepts/foundations/activation/apis/getting-started/querying-data-products/measure-and-dimension-behavior.md) — how measures and dimensions behave in queries.
* [Cross-model queries](/concepts/foundations/activation/apis/getting-started/querying-data-products/cross-model-queries.md) — join direction, fan-out, and join hints.
* [GraphQL vs REST](/concepts/foundations/activation/apis/getting-started/querying-data-products/graphql-vs-rest.md) — compare capabilities and trade-offs.


---

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