NHibernate QueryOver API ↔ SQL Server Pagination: ensuring deterministic paging with .OrderBy()

NHibernate QueryOver API ↔ SQL Server Pagination

When implementing server‑side paging with NHibernate’s QueryOver, the typical pattern is .OrderBy() followed by .Skip(n) and .Take(m). The goal is to retrieve page n of a stable result set without duplicates or gaps. The constraints are that the underlying SQL dialect may translate these calls into different constructs (LIMIT/OFFSET, TOP/FETCH, or ROW_NUMBER), and that a missing or unstable .OrderBy() can lead to non‑deterministic results. The uncertainty lies in whether NHibernate enforces a deterministic order when the same .OrderBy() expression is used across different database back‑ends, and how large .Skip() values affect performance and correctness on each dialect.

Specific questions:

• Does NHibernate guarantee that a given .OrderBy() expression yields a stable ordering across all supported SQL dialects?
• Are there documented performance regressions when using large .Skip() values on PostgreSQL or Oracle?
• What best practices exist for combining .OrderBy() with .Skip() and .Take() to avoid duplicate or missing rows in paging scenarios?