CSharpDB v4.0.3

version4.0.3

version4.0.3 removes the single-page B-tree payload limit, allowing large SQL values and Collection documents to span multiple 4 KiB pages safely. It also improves the Windows Desktop Admin experience with native file and folder dialogs throughout local path workflows.

Fixed

• B-tree payloads larger than the 4,075-byte inline limit are now stored in linked overflow pages instead of failing when a leaf page cannot be split.
• Overflow-backed values work across point and snapshot reads, cursor scans, inserts, replacements, deletes, rollback, leaf splits, checkpoints, and database reopen.
• Replaced and deleted overflow chains are reclaimed for reuse, while rejected duplicate inserts and missing-key replacements avoid allocating overflow pages.
• Storage diagnostics recognize overflow pages and validate reference metadata, page types, bounds, lengths, and cycles so corrupt chains are reported clearly.
• Failed implicit Collection writes now release the write gate correctly, allowing later writes to continue.

Desktop Admin

• The Windows desktop shell now provides native Open, Save, and Select Folder dialogs for databases, code-module workspaces, compare/deploy sources and targets, pipeline inputs and outputs, backups, restores, migration backups, imports, exports, and table archives.
• Open and Save dialogs apply the appropriate file filters, default extensions, existence checks, and overwrite prompts. Cancellation is handled safely, and manual path entry remains available for browser-hosted Admin sessions and relative paths.
• Native Browse controls now appear only when the page is running inside the trusted Desktop WebView, avoiding inactive controls when the desktop child host is opened in a regular browser.
• Desktop startup now locates the Admin host reliably in installed, development, and published layouts.

Compatibility

• Existing format-v1 databases remain readable and are durably upgraded to format v2 before the next write is committed; read-only opens do not rewrite the file.
• Once upgraded to format v2, a database requires a CSharpDB version that understands tagged overflow references. Back up the database before upgrading if rollback to an older binary may be required.
• Explicitly tagged leaf cells keep ordinary inline values unambiguous, including values whose bytes resemble an overflow reference.

Performance and Validation

• Added coverage for 10–20 KB SQL, Collection, and direct B-tree values across CRUD, rollback, cursor scans, page splits, checkpoint/reopen, page reuse, format migration, and corruption detection.
• BenchmarkDotNet comparisons found no measurable steady-state regression for existing inline workloads.
• A roughly 6 KB overflow value measured 2.365 ms per durable insert and 4.595 microseconds per hot primary-key read on the benchmark machine. The previous version cannot complete this workload.
• Corrected the B-tree cursor benchmark to retain the final root page after splits so seek measurements exercise the intended tree path.
• Final Release validation passed all 2,127 tests. Desktop Admin Debug/Release builds, JavaScript capability validation, isolated host launches, signed Store package generation, and a packaged Open/Save/Select Folder smoke test also completed successfully.