A data structure where the ‘innermost’ dimension is not a time dimension. Contrast with flat, time series.

data flow

A collection of one or more data sets sharing the same structure.


A data set that is not grouped using SeriesKeys.


Data and metadata.

information model

A description of how information is organized, providing semantics: specific terms, their meanings, and their relationships. The SDMX IM is one information model.


Information about data. For instance, [1.2, 3.4, 4.5] are data points, or observations. Metadata for these data might include:

  • what concept is being measured,

  • the units for the measurements,

  • labels in one or more dimensions for what the three points means, or

  • info about how the data was produced, and by whom.

time series

A data structure where the ‘innermost’ dimension—the one that varies from one observation to the next—is time-related. Contrast with cross-sectional, flat.