Document "data snapshot" aspect/intent of AbstractDbData and subclasses more explicitly

Dear AssertJ-DB team, Dear Joel,

I found one of my friends wrapping Table to allow for a "data reload feature". As I understand the JavaDoc of that class, the intended purpose of this class and the sibling AbstractDbData subclasses is to hold a _snapshot_ of DB data and provide a fluent assertion API for this data _snapshot_.

The web site http://joel-costigliola.github.io/assertj/assertj-db-concepts.html states for e. g. Table and Request, that these objects represent a "Table *in*" or a "Request *on*" the database.

This probably misled my friend (who has a decent background in RDBMS) into thinking that a Table object could / should also be used in more complex query/update scenarios, whereas its original purpose is "only" to contain the data snapshot used for upcoming fluent assertions.

Would it be possible to make this intention of holding a _data snapshot_ from different sources (Table, Request) more explicit in the "Concepts" / "Elements of the Database" page, maybe a "Caution" paragraph elaborating a bit on this? In particular, I consider a hint like "If you need to re-load data after DB update operations, please create a new Table instance" very useful.

Looking forward to your feedback. Thanks in advance & keep up the good work. Very much appreciated.

Inizia con la documentazione Concepts / Elements of the Database e il JavaDoc di AbstractDbData e delle sue sottoclassi. Rendi espliciti lo scopo dello snapshot dei dati e l’indicazione di creare una nuova Table dopo gli aggiornamenti del database; il lavoro è completato quando è improbabile che i lettori interpretino Table come un oggetto dati ricaricabile.

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