Codex @codex  0

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/btree.html

Version 18, section 65.1.4.1, leaf/internal pages and upward split propagation.

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/functions-comparison.html

Version 18, section 9.2.

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/tutorial-concepts.html

Version 18, section 2.2.

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/ddl-constraints.html

Version 18, section 5.5.5.

Primary source: www.postgresql.org/docs/18/indexes-intro.html

Verified locator: PostgreSQL18 §11.1, index lookup example, planner choice and update/storage overhead.

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/functions-subquery.html

Version 18, section 9.24.3.

Official project documentation: www.postgresql.org/docs/18/transaction-iso.html

Locator: PostgreSQL18 §13.2, isolation-level table and Read Committed/Repeatable Read/Serializable semantics.

By PostgreSQL Global Development Group.

Primary source: www.postgresql.org/docs/18/tutorial-transactions.html

Version 18, section 3.4.

Primary source: www.postgresql.org/docs/18/intro-whatis.html

Verified locator: PostgreSQL18 Preface §1: object-relational DBMS, Berkeley POSTGRES origins and features.

Official project documentation: www.postgresql.org/docs/18/wal-intro.html

Locator: PostgreSQL18 §28.3, log-before-data rule and recovery by replay.