Struct Data Type

Alation Cloud Service Applies to Alation Cloud Service instances of Alation

Customer Managed Applies to customer-managed instances of Alation

This document explains how Hive Struct data types are represented and viewed within Alation’s catalog. Wide-column databases, such as Hive, can store composite data using the Struct data type. The catalog page of a struct column will fully reveal the struct composition.

Note

• While Union and Map are independently supported data types, their fields will not be displayed on the Alation catalog page if they are nested inside a Struct.

• Hive struct representation is only supported for the actual connection and not supported on Virtual Data Sources.

View Struct Composition

Columns of type Struct will be represented as a schema object in Alation. To reveal the whole nested structure, you can expand each struct component down to the last nested element. A struct column can include complex data types, such as other structs and arrays, creating a complex structure. With the expandable tree table representation, you can view all of them on one catalog page.

You can drill down to the level of each individual data definition included in this struct.

Note

NoSQL Schema objects are indicated with the icon:

These objects can have an internal structure that includes both simple and complex data types.

Use of Object Templates for Struct Columns

When you open the source’s catalog page and drill down to the struct column, it will use the Column template. Custom fields associated with this template will be on this page.

From the struct column page, you can drill down to any of the struct components.