A dataset is a collection of related data that is stored in a denormalized, yet highly compressed form. For each platform license, your organization can have a maximum of 250 million rows of data stored for all registered datasets combined.
Wave Analytics applies one of the following types to each dataset field:
- A date can be represented as a day, month, year, and, optionally, time. You can group, filter, and perform math on dates.
- A dimension is a qualitative value, like region, product name, and model number. Dimensions are handy for grouping and filtering your data. Unlike measures, you can’t perform math on dimensions. To increase query performance, Wave Analytics indexes all dimension fields in datasets.
- A measure is a quantitative value, like revenue and exchange rate. You can do math on measures, such as calculating the total revenue and minimum exchange rate.
For each dataset that you create, you can apply row-level security to restrict access to records in the dataset.
Before you create a dataset, verify that the source data contains at least one value in each column. Columns with all null values won't be created in datasets and can't be referenced in dataflows, lenses, or dashboards. Consider providing a default value for null values, like "n/a" or "empty."