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Relational Algebra: Selection, Projection, Join, Union

This generated surface maps a learner-facing curriculum unit to its canonical source routes.

Curriculum surface​

  • Open learner-facing unit
  • Curriculum path: content/curriculum/architecture/semester-06-databases-distributed/module-01-relational-databases-sql/concepts/cluster-01-the-relational-model/03-relational-algebra-selection-projection-join-union-primary.md
  • App: architecture
  • Semester: semester-06-databases-distributed
  • Module: module-01-relational-databases-sql
  • Unit kind: concept
  • Curation level: module_curated

Learning objectives​

  • Explain Relational Algebra: Selection, Projection, Join, Union using the language of schema, constraints, query semantics, and tradeoffs instead of isolated SQL syntax.
  • Connect the learner-facing explanation of Relational Algebra: Selection, Projection, Join, Union to real database behavior you can inspect in a running system or reason about from execution plans.
  • Use database-system-concepts to tie relational ideas back to formal models, practical query behavior, and design decisions.

Prerequisites​

  • Comfort with sets, functions, and the idea of data modeling from earlier semesters.

Source books​

  • database-system-concepts

Source routes​

Database System Concepts​

  • /books/database-system-concepts via Silberschatz: Relational algebra, part 1, Silberschatz: Relational algebra, part 2, Silberschatz: Relational algebra, part 3, Silberschatz: Relational algebra, part 4

Supporting curriculum routes​

No supporting curriculum routes linked yet.

External enrichment​

  • PostgreSQL Documentation: SELECT (official_docs_companion) - Useful when the learner needs exact SQL query semantics and processing order, not another high-level summary.
  • PostgreSQL Tutorial (read_if_stuck) - Good for reconnecting formal relational ideas to runnable SQL examples without leaving the module context.

AI companion modes​

  • Explain simply
  • Socratic tutor
  • Challenge my understanding
  • Diagnose my confusion
  • Connect forward / backward

Source-of-truth note​

This teaching unit is learner-facing guidance. Its canonical source backbone is the referenced book database-system-concepts, and outside material should only clarify or strengthen that backbone.