The Concepts: $1.$ Object Oriented Database Systems $2.$ Blockchain Databases $3.$ NoSQL Databases $4.$ Big Data Analytics The Questions: For each of the above concepts and in the context of database systems, briefly and clearly provide i$)$ The key defining aspects of the concept $($i$.$e$.$ what is it all about$)$ ii$)$ Key reasons$/$potential supporting belief in the concepts $($i$.$e$.$ expected benefits$/$advantages$)$ iii$)$ Reported success$/$failure of the concept in the real world iv$)$ The likely future of the concept v$)$ Examples of commercial products