By default, what metadata shows for each field?

The correct choice provides a comprehensive overview of the essential metadata displayed for each field in a data set. By default, this metadata includes the field name, which identifies the specific variable in the dataset; the data type, which indicates the kind of data stored in that field (such as string, integer, etc.); the length, which specifies the maximum number of characters or digits that can be held in that field; and the source, which reveals where the data is coming from. This information is crucial for understanding the structure of the data and how it can be used in analysis.

In contrast, the other choices do not reflect the full range of metadata associated with each field. For example, while data values and data length may be informative, they do not capture essential identifying aspects like the field name or type. Similarly, the option mentioning calculated fields only disregards the broader context of standard field metadata. Lastly, field indices and constraints focus on database management aspects rather than the foundational metadata necessary for data analysis. Thus, the selected correct answer encapsulates the key elements that users typically seek when reviewing field metadata in a dataset.