• Tables:
    • Inferior database systems.
    • Sophisticated database systems, realizing that an operation needs to lock many rows: Lock escalation

  • Pages:
    • E.g. Sybase, back in the 80s.
    • Easy to do. The database system has data structures tracking pages anyway.
    • But if you want to lock one row, and you lock the entire page instead, there will be spurious lock conflicts: You've locked all the rows on the page.