In a relational model,
a schema is something which specifies the name and data type of each field.
The word "schema" is also used in "conceptual schema", "physical schema" and "external schema".
What do "schema" mean separately in the above two cases? Are they related?
Are they related to the "schema" in cognitive psychology?
Is "schema" used in other areas of computer science, such as artificial intelligence, programming languages, ...?
What does "schema" mean in computer science besides database?
Thanks!