To put it simple,
- DACPAC – Only Schema
- BACPAC – Schema + Data (Native BCP format, previously compressed JSON)
They can be interacted using SSMS, PowerShell and .NET. It is the most used method of backup and restore SQL Azure database.
You can rename either of the packages to a *.zip extension to see the XML content, however it is not the same as unpacking them.
If you have DAC installed on the machine, you can “Unpack” the file by right click contest menu entry.
DACPACs can be extracted through commandline using sqlpackage.exe
e.g. “C:\Program Files (x86)\Microsoft SQL Server\110\DAC\bin\sqlpackage.exe” /action:Extract /OverwriteFiles:False /tf:”C:\MyTestDB.dacpac” /SourceConnectionString:”Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=TailSpinToys;Data Source=SQL2012SERVER”
More info on sqlpackage – http://msdn.microsoft.com/en-us/library/hh550080%28v=vs.103%29.aspx