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What is the difference between graph-based databases and object-oriented databases?
I'm finding a database which can store in-memory data structure naturally. In other words, the object graph. I once have used db4o, it's quite good but somewhat lacking. And I found a new concept of database, the 'graph-database'. But I felt they're similar things just have difference terms. This means I don't know the difference. What are the key differences?
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A graph database is a kind of NoSQL database that uses graph structures with nodes, edges, and properties to represent and store information. General graph databases that can store any graph are distinct from specialized graph databases such as triplestores and network databases. Definition
An object database (also object-oriented database) is a database model in which information is represented in the form of objects as used in object-oriented programming. Object databases are a niche field within the broader DBMS market dominated by relational database management systems (RDBMS). Object databases have been considered since the early 1980s and 1990s but they have made little impact on mainstream commercial data processing, though there is some usage in specialized areas. Definition
You'll find good answers in this Stack Overflow thread: What is the difference between graph-based databases and object-oriented databases?