# MDX API

The MDX API enables Cube to connect to [Microsoft Excel][ref-excel]. It derives
its name from [multidimensional data expressions][link-mdx], a query language
for OLAP in the Microsoft ecosystem.

Unlike [Cube Cloud for Excel][ref-cube-cloud-for-excel], it only works with Excel
on Microsoft Windows. However, it allows using the data from the MDX API with the
native [PivotTable][link-pivottable] in Excel.

<InfoBox>

Available on [Enterprise and above plans](https://cube.dev/pricing).
Also requires the M [deployment tier](/product/administration/pricing#deployment-tiers).

</InfoBox>

<WarningBox>

The MDX API is currently in preview.

</WarningBox>

Key features:

- <b>Direct connectivity:</b> Connect Excel directly to Cube Cloud using standard XMLA protocols.
- <b>Advanced analytical functions:</b> Utilize the power of MDX to execute sophisticated queries that include slicing, dicing, drilling down, and rolling up of data.
- <b>Real-time access:</b> Fetch live data from Cube Cloud, ensuring that your analyses and reports always reflect the most current information.

## Configuration

<WarningBox>

While the MDX API is in preview, your Cube account team will enable and configure it for you.

</WarningBox>

To enable or disable the MDX API on a specific deployment, go to <Btn>Settings</Btn>
in the Cube Cloud sidebar, then <Btn>Configuration</Btn>, and then toggle the
<Btn>Enable MDX API</Btn> option.

### Performance considerations

To ensure the best user experience in Excel, the MDX API should be able to respond to
requests with a subsecond latency. Consider the following recommendations:

- The [deployment][ref-deployment] should be collocated with users, so deploy it a region
that is closest to your users.
- Queries should hit [pre-aggregations][ref-pre-aggregations] whenever possible. Consider
turning on the [rollup-only mode][ref-rollup-only-mode] to disallow queries that go
directly to the upstream data source.
- If some queries still go to the upstream data source, it should respond with a
subsecond latency. Consider tuning the concurrency and quotas to achieve that.

### Date hierarchies

By default, the MDX API creates additional hierarchies for all [time dimensions][ref-time-dimensions] and organizes them in a separate folder called "Calendar" for each dimension.
The following hierarchies are created:

```
- Dimension Calendar:
  - Year
  - Quarter
  - Month
  - Day
- Dimension Calendar Weeks:
  - Year
  - Week
- Dimension Calendar Quarter of Year:
  - Quarter
- Dimension Calendar Year:
  - Year
```

The **Calendar Quarter of Year** and **Calendar Year** hierarchies are particularly useful in Excel because they allow you to filter your data without needing to drill down or expand all levels.
You can use them as slicers while placing other dimensions on the axes.

You can set the `CUBE_MDX_CREATE_DATE_HIERARCHIES` environment variable to `false` to disable this behavior.

### Measure format

The MDX API respects the [`format` parameter][ref-measure-format] of measures so that the
values are displayed accordingly in Excel, i.e., `percent` formats values as percentages
and `currency` formats values as monetary values.

Currency formatting is locale-aware and responds to the language configuration set via
the `CUBE_XMLA_LANGUAGE` environment variable.

## Using MDX API with Excel

<InfoBox>

The MDX API works only with [views][ref-views], not cubes.

</InfoBox>

The following section describes Excel-specific configuration options.

### Dimension hierarchies

MDX API supports dimension hierarchies. You can define multiple hierarchies.
Each level in the hierarchy is a dimension from the view.

```yaml
views:
  - name: orders_view
    description: "Data about orders, amount, count and breakdown by status and geography."
    meta:
      hierarchies:
        - name: "Geography"
          levels:
            - country
            - state
            - city
```

<InfoBox>

For historical reasons, the syntax shown above differ from how
[hierarchies][ref-hierarchies] are supposed to be defined in the data model.
This is going to be harmonized in the future.

</InfoBox>

### Dimension keys

You can define a member that will be used as a key for a dimension in the cube's model file.

```yaml
cubes:
  - name: users
    sql_table: USERS
    public: false

    dimensions:
      - name: id
        sql: "{CUBE}.ID"
        type: number
        primary_key: true

      - name: first_name
        sql: FIRST_NAME
        type: string
        meta:
          key_member: users_id
```

### Dimension labels

You can define a member that will be used as a label for a dimension in the cube's model file.

```yaml
cubes:
  - name: users
    sql_table: USERS
    public: false

    dimensions:
      - name: id
        sql: "{CUBE}.ID"
        type: number
        meta:
          label_member: users_first_name
```

### Custom properties

You can define custom properties for dimensions in the cube's model file.

```yaml
cubes:
  - name: users
    sql_table: USERS
    public: false

    dimensions:
      - name: id
        sql: "{CUBE}.ID"
        type: number
        meta:
          properties:
            - name: "Property A"
              column: users_first_name
            - name: "Property B"
              value: users_city
```

### Measure groups

MDX API supports organizing measures into groups (folders). You can define measure groups in the view's model file.

```yaml
views:
  - name: orders_view
    description: "Data about orders, amount, count and breakdown by status and geography."
    meta:
      folders:
          - name: "Folder A"
            members:
              - total_amount
              - average_order_value
          - name: "Folder B"
            members:
              - completed_count
              - completed_percentage
```

<InfoBox>

For historical reasons, the syntax shown above differ from how
[folders][ref-folders] are supposed to be defined in the data model.
This is going to be harmonized in the future.

</InfoBox>

## Authentication and authorization

Authentication and authorization work the same as for the [SQL API](/product/apis-integrations/sql-api/security).

[ref-excel]: /product/configuration/visualization-tools/excel
[link-mdx]: https://learn.microsoft.com/en-us/analysis-services/multidimensional-models/mdx/multidimensional-model-data-access-analysis-services-multidimensional-data?view=asallproducts-allversions#bkmk_querylang
[link-pivottable]: https://support.microsoft.com/en-us/office/create-a-pivottable-to-analyze-worksheet-data-a9a84538-bfe9-40a9-a8e9-f99134456576
[ref-cube-cloud-for-excel]: /product/apis-integrations/microsoft-excel
[ref-hierarchies]: /product/data-modeling/reference/hierarchies
[ref-folders]: /product/data-modeling/reference/view#folders
[ref-views]: /product/data-modeling/concepts#views
[ref-deployment]: /product/deployment/cloud/deployments
[ref-pre-aggregations]: /product/caching/using-pre-aggregations
[ref-rollup-only-mode]: /product/caching/using-pre-aggregations#rollup-only-mode
[ref-measure-format]: /product/data-modeling/reference/measures#format
