Data Model

Key/Value

Heroic uses a key/value data model, where each key is comprised of a “unique set of tags and resource identifiers” that correspond to a single series. In this context, we define tags as the database data that can be indexed and will be retained within the database. Additionally, each tag also has its corresponding-time series stored with the data. Tags are thus used in complex queries for both filtering and aggregations, as described by the GitHub Documentation. On the other hand, a Resource Identifier is data that cannot be indexed. However the data itself is still stored with this corresponding-time series. Thus, the purpose of resource identifiers itself is to ensure that data which is constantly changing can still be stored and accessed as per its time-series. As the GitHub documentation gives as example, if the hostname field were to change often, rather than retaining the field, for the purpose of maintaining time-series data as the documentation describes, we would keep hostname as a Resource Identifier and not a tag. As such, resource identifiers are used for querying based off of aggregations.