When an information link or a data table from a data connection is to be added to the analysis as a new data table, you have the option to either load all data at once, or to load data on demand only. Your analysis can benefit from on-demand loading when you have access to massive amounts of data, but you only need to work with some parts of the data at a time. When setting up an on-demand data table you can specify conditions based on one or more other data tables to control what to load. You can also start by letting an on-demand data table be the first (or only) data table in the analysis if its input is defined by a document property.
See also:
Example of Marking Controlled On-Demand Details Visualization
Example of Property Controlled On-Demand Data
How to Insert Multiple Data Tables to the Analysis