Issue Overview: Upgrading System.Data.SQLite with SEE Breaks Legacy Database Access The core issue arises when upgrading from an older version of System.Data.SQLite (1.0.98) with custom AES-256 encryption to a newer version (1.0.118) using SQLite Encryption Extension (SEE 3.42.0). Databases encrypted with the legacy library fail to open with the upgraded library despite attempts to maintain…
Understanding the sqlite_sequence Table and Its Role in Schema Export The sqlite_sequence table is an internal SQLite table that is automatically created and managed by SQLite when a table with an AUTOINCREMENT column is defined. Its primary purpose is to keep track of the highest sequence number used in any AUTOINCREMENT column, ensuring that each…
Understanding the SQLITE_THREADSAFE Discrepancy Between Compilation and Runtime Compilation Settings vs. Runtime Behavior of SQLITE_THREADSAFE The core issue involves a mismatch between the SQLITE_THREADSAFE compile-time setting and the value returned by the sqlite3_threadsafe() API at runtime. A developer compiled SQLite with -DSQLITE_THREADSAFE=2 in the Makefile.msc for a Windows build, confirmed via PRAGMA COMPILE_OPTIONS that the…
Understanding the Need for Database Comparison and Synchronization When working with SQLite databases, especially in the context of software development, it is common to encounter scenarios where you need to compare two databases to identify differences in their schemas or data. This need often arises during software updates, where the database schema may evolve to…
Issue Overview: Mixed-Case JSON Key Mismanagement in SQLite ETL Pipelines The core issue revolves around processing JSON data with inconsistently cased keys during Extract-Transform-Load (ETL) operations in SQLite. Legacy systems or applications that serialize JSON with case-insensitive key comparisons (e.g., cJSON-based tools) often produce datasets where keys like "UserId," "userid," and "USERID" coexist. SQLite’s native…
SQLite SEE Encryption: Capabilities and Cross-Platform Compatibility SQLite is a lightweight, serverless, and self-contained database engine widely used in embedded systems, mobile applications, and desktop software. One of its powerful features is the SQLite Encryption Extension (SEE), which provides robust encryption capabilities for SQLite databases. However, implementing SEE across multiple platforms, such as .NET, Android,…
Understanding How changeset_apply() Manages Auto-Increment Primary Keys in INSERT/DELETE Operations The changeset_apply() function in SQLite is a powerful tool for applying a set of changes (inserts, updates, and deletes) to a database. However, its behavior when dealing with tables that have an auto-incrementing integer primary key (PK) can be nuanced and requires a deep dive…
Understanding Valgrind’s "Still Reachable" Memory in SQLite3 CLI Valgrind’s "Still Reachable" Memory Warnings in SQLite3 CLI The core issue revolves around Valgrind reporting "still reachable" memory blocks when running the SQLite3 command-line interface (CLI). These reports indicate that memory allocations persist at program termination but are not classified as leaks (i.e., "definitely lost," "indirectly lost,"…
Understanding SQLite WASM Corruption on OPFS in Chrome Extensions The integration of SQLite WASM with the Origin Private File System (OPFS) in Chrome extensions has introduced a unique set of challenges, particularly around database corruption. This issue manifests as sporadic corruption events, often resulting in the error "SQLITE_CORRUPT: sqlite3 result code 11: database disk image…
Issue Overview: Intermittent Column Mismatch During High-Frequency Database Operations The core issue reported involves an intermittent System.Data.SQLite.SQLiteException with the message "Column ‘ORD_SERIAL_NO’ does not belong to table" in a high-throughput C# application using SQLite 3.40.0. The application processes real-time trading data at rates of 300-400 trades per second, with frequent insertions and deletions. The error…