Like in all other languages, symbols represent references to a collection of standard objects, properties, and functions. They are a special extension file themselves with the typical .app naming convention and are used to maintain object reference consistency while compiling, and they also populate valid IntelliSense entries.
Symbols are typically stored inside the database in a BLOB field in JSON for each object record. It is worth mentioning that in multitenancy, the Object Metadata table is part of the application database, so in customer tenant databases there are no system symbols or metadata stored, only data.
With Dynamics 365 Business Central, symbols are already preloaded inside the application database, and ...
