Issue Overview: LSM1 Log Space Reclamation Due to Incorrect Synced ID Handling The core issue revolves around the lsmFsReadSyncedId() function in the LSM1 storage engine, which is responsible for reading the synced snapshot ID from the database metadata. The bug manifests when the function incorrectly reads the synced ID, leading to a persistent mismatch between…
Query Structure Triggering Assertion Failure in Aggregation Logic The core issue involves an assertion failure (Assertion 0′ failed) in SQLite’s agginfoPersistExprCb` function when executing a specific query containing nested aggregates, window functions, and correlated subqueries. The failure occurs under these conditions: A multi-table join (v0 AS a0 JOIN v0 AS a1) with grouping (GROUP BY…
Schema and Insertion Logic Overview The core issue revolves around the insertion of data into an SQLite database where the application reports successful insertions, but only a portion of the data is actually written to the database. The schema in question involves two tables: Blasting_Record_Head and Blasting_Record_Detail. The Blasting_Record_Detail table has a foreign key relationship…
Issue Overview: SQLite’s Real-to-Integer Conversion Erases Negative Zero Sign The core challenge arises from SQLite’s internal optimization for numeric storage, which converts floating-point values to integers when possible. This process inadvertently discards the sign of negative zero (-0.0) because the equality check used in the conversion logic treats 0.0 and -0.0 as identical. While SQLite…
Understanding the Assertion Failure in sqlite3VdbeExec The core issue revolves around an assertion failure in the sqlite3VdbeExec function, which is a critical part of SQLite’s virtual machine responsible for executing bytecode generated from SQL statements. The failure occurs when executing a specific sequence of SQL queries involving table creation, view creation, and a complex SELECT…
Understanding Deferrability in SQLite Foreign Key Constraints Issue Overview Deferrability in the context of foreign key constraints refers to the ability to postpone the enforcement of these constraints until the transaction is committed. This feature is particularly useful in complex transactions where the order of operations might temporarily violate foreign key constraints, but the final…
Issue Overview: Read-Only Database Errors During Schema Version Checks The error attempt to write a readonly database during execution of PRAGMA schema_version represents a conflict between SQLite’s internal mechanisms and the permissions/state of the database environment. Though PRAGMA schema_version is designed to return an integer indicating the schema version (a read operation), this error implies…
Database Connection Discrepancy: Mismatched Filenames and Open Modes Issue Overview: Table Not Found When Executing Query in Custom C Application The core issue arises when a SQLite query that successfully executes in the sqlite3 command-line interface fails in a custom C application with the error "no such table: TermNoList". This discrepancy occurs despite identical query…
Understanding the Assertion Failure in sqlite3ExprAffinity The core issue revolves around an assertion failure in the sqlite3ExprAffinity function, which occurs during the execution of a trigger after renaming a column in a table. The assertion failure is triggered by a specific sequence of SQL operations: creating two tables (v0 and v1), defining a trigger (t)…
Understanding the Core Failure: Cursor Initialization in Window Function Contexts The assertion failure pC!=0 in sqlite3VdbeExec arises when SQLite attempts to access a database cursor (VdbeCursor) that has not been properly initialized or has been prematurely closed during query execution. This occurs specifically in queries involving window functions, aggregation with GROUP BY, and collation-sensitive views…