The Game of the Year Edition of Dragon Age: Inquisition contains:
Dragon Age: Inquisition (base game)
Dragon Age: Inquisition - Jaws of Hakkon (DLC)
Dragon Age: Inquisition - The Descent (DLC)
Dragon Age: Inquisition - Trespasser (DLC)
Dragon Age: Inquisition - Spoils of the Qunari (DLC)
Dragon Age: Inquisition - Spoils of the Avvar (DLC)
Dragon Age: Inquisition - Deluxe Edition Upgrade (DLC)
Dragon Age: Inquisition - Deluxe Edition Upgrade consists of these downloadable contents not available as standalone DLCs:
Dragon Age: Inquisition - Deluxe Edition Items
Flames of the Inquisition Weapons
Flames of the Inquisition Armored Mount
Flames of the Inquisition Armor
The retail release only contains the base game on the disc, while the rest needs to be downloaded. The voucher for downloading the Game of the Year Edition content is valid for only two years since the game's release (until October 17th, 2017).

This game release is also slipstreamed with these free downloadable contents which can also be downloaded independently of the voucher's redeem code. These include:
Dragon Age: Inquisition - Dragonslayer (DLC)
Dragon Age: Inquisition - The Black Emporium (DLC)
Dragon Age: Inquisition - Destruction Multiplayer Expansion (DLC)
When entering the redeem code from retail release, or downloading the digital release, all the above mentioned DLCs are included in the package as a full set, even those free DLCs that could've been downloaded on their own.