Databases
Database Analogies
Collected by Daphne Miedema — Textbook Hellerstein, J. M., & Stonebraker, M. (2005). Readings in Database Systems. 4 ed. MIT Press.
Data storage and indexing
Within-Database
Draws parallels to processing as done in relational databases.
| Symbol | Concept |
|---|---|
| JSON structure | schema |
| defining what to see at runtime | projection operation |
| schema on read | relational operation" |
How reading from JSON is similar to RDBMS projection
"JSON can be viewed in one of three ways. [...] As a mechanism for “schema on read”. In effect, the schema is very wide and very sparse, and essentially all users will want some projection of this schema. When reading from a wide, sparse schema, a user can say what he wants to see at run time. Conceptually, this is nothing but a projection operation. Hence, ’schema on read” is just a relational operation on JSON-encoded data. In summary, JSON is a reasonable choice for sparse data. In this context, I expect it to have a fair amount of “legs”. On the other hand, it is a disaster in the making as a general hierarchical data format. I fully expect RDBMSs to subsume JSON as merely a data type (among many) in their systems."
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A notional machine is a pedagogic device to assist the understanding of some aspect of programs or programming. To something along the lines of A notional machine is a pedagogical tool designed to support the understanding of programs, programming, and other aspects of computing such as databases.
