Digital Digressions by Stuart Sierra

Let’s have the database models strut down the runway:
Relational (SQL):

Data consist of rows in tables.
Each row has multiple columns.
Each column has a fixed type.
Queries use filters and joins.
Fixed schema is defined separately from the data.
User-defined indexes improve query performance.
Robust transaction/data-integrity support.

Graph (RDF):

Data consist of nodes and labeled links between them.
Nodes may have type information.
Optional schema [...]

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