---
title: MLDataTable.Aggregator
framework: createml
role: symbol
role_heading: Structure
path: createml/mldatatable/aggregator
---

# MLDataTable.Aggregator

A collection of column operations you can use with a data table’s group method.

## Declaration

```swift
struct Aggregator
```

## Overview

Overview Use one or more MLDataTable.Aggregator instances when you use the group(columnsNamed:aggregators:) method. Each aggregator performs a sequence of one or more MLDataTable.Aggregator.Operations for a single column. Each operation makes a new column in the new data table generated by the method.

## Topics

### Creating an aggregator

- [init(operations:of:)](createml/mldatatable/aggregator/init(operations:of:).md)

### Configuring an aggregator

- [columnName](createml/mldatatable/aggregator/columnname.md)
- [operations](createml/mldatatable/aggregator/operations-swift.property.md)
- [MLDataTable.Aggregator.Operations](createml/mldatatable/aggregator/operations-swift.enum.md)

## Relationships

### Conforms To

- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Aggregating rows

- [group(columnsNamed:aggregators:)](createml/mldatatable/group(columnsnamed:aggregators:).md)