With Cardano-cli
you can only query your UtxOs to get the corresponding tx hash. Unfortunately, there is nothing to go deeper and get additional information.
I dont' understand what you mean by "are not directly retrievable from the ledger", but yes, db-sync
has access to this information.
The purpose of Cardano DB Sync is to follow the Cardano chain and take
information from the chain and an internally maintained copy of ledger
state. Data is then extracted from the chain and inserted into a
PostgreSQL database. SQL queries can then be written directly against
the database schema or as queries embedded in any language with
libraries for interacting with an SQL database.
However, you need some non negligible resource to run db-sync
. What Blockfrost
does is "just" to wrap a web API around the DB in order for everyone to get an easy access to it. Blockfrost
is the easiest way to retrieve your sender address.