DP44/enriched-qwen3-coder-next/DataPRO/DbAPI/SPCaching.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
DataPRO/DbAPI/SPCaching/SPCache.cs	2026-04-16T04:26:17.028428+00:00	Qwen/Qwen3-Coder-Next-FP8	1	d93a7e3ae4a08e22

SPCaching

1. Purpose

The SPCache class serves as a lightweight data container for caching the mapping between client and database versions to a specific stored procedure version. Its role is to avoid redundant version-resolution logic—once the appropriate stored procedure version has been determined for a given (ClientVersion, DbVersion) pair, it can be reused by storing it in an SPCache instance. This is intended for scenarios where version compatibility decisions are expensive or frequently repeated, and where the mapping is assumed stable after initial resolution.

2. Public Interface

The class exposes only public auto-implemented properties; there are no methods or constructors defined.

• int ClientVersion { get; set; }
  Stores the application or client version used as input to the version-resolution logic.

• int DbVersion { get; set; }
  Stores the database version used as input to the version-resolution logic.

• int StoredProcedureVersion { get; set; }
  Stores the resolved stored procedure version corresponding to the ClientVersion and DbVersion.

3. Invariants

• The class itself enforces no invariants beyond the type of its properties (all are non-nullable int properties with default values of 0 if unset).
• There is no validation or consistency check on the relationship between ClientVersion, DbVersion, and StoredProcedureVersion. For example, no rule enforces that StoredProcedureVersion must be ≤ ClientVersion or match any particular schema.
• The documentation implies that once a mapping is determined, it is assumed stable ("once this has been determined we don't need to determine it again ... usually"), but this is a usage convention, not a runtime invariant.

4. Dependencies

• No external dependencies: The file contains no using directives, indicating no runtime dependencies on other namespaces or libraries.
• Depended on by: Not visible in this source file. Based on the namespace (DbAPI.SPCaching) and class purpose, it is likely consumed by components responsible for database interaction or stored procedure dispatch (e.g., a data access layer), but such consumers are not specified here.

5. Gotchas

• No equality or hashing support: The class does not override Equals, GetHashCode, or implement IEquatable<SPCache>. Two instances with identical property values will not be considered equal by reference-based comparison unless explicitly handled by consumers.
• Mutable by design: All properties are public set, so the cache entry can be modified after creation. This may lead to stale or inconsistent entries if reused carelessly.
• No version conflict detection: If the same (ClientVersion, DbVersion) pair maps to multiple StoredProcedureVersion values over time (e.g., due to schema changes), the cache provides no mechanism to invalidate or detect such mismatches.
• Ambiguous version semantics: The documentation does not clarify how StoredProcedureVersion is derived (e.g., is it the minimum, maximum, or exact match version?), nor whether negative or zero values are valid. Consumers must infer this from external logic.
• Thread-safety not addressed: The class has no synchronization primitives; concurrent access to a shared instance is unsafe unless managed externally.