SQLite3.c Compilation Error Due to Mixed Declarations and Code The core issue revolves around a compilation error encountered when attempting to build SQLite3 using the C89 standard. The error message specifically points to a violation of the ISO C90 (commonly referred to as C89) standard, which prohibits mixed declarations and code within a function. The…
FTS5 Trigram Tokenizer Fails to Match Partial Strings The issue at hand involves the FTS5 (Full-Text Search) extension in SQLite, specifically when using the trigram tokenizer. The problem manifests when attempting to perform a search using the LIKE operator on a virtual table that has been configured with the trigram tokenizer. Despite the presence of…
SQLite User Authentication and Precompiled DLLs SQLite is a lightweight, serverless, and self-contained database engine that is widely used in applications requiring embedded database functionality. One of the lesser-known features of SQLite is its ability to support user authentication through the SQLITE_USER_AUTHENTICATION compile-time option and the sqlite3_user_authenticate() interface. This feature allows developers to implement password-protected…
RETURNING Clause Ignores AFTER Trigger Modifications The RETURNING clause in SQLite is a powerful feature that allows developers to retrieve values from rows affected by INSERT, UPDATE, or DELETE operations directly within the same statement. However, its behavior in the presence of triggers, particularly AFTER triggers, can be counterintuitive. Specifically, the RETURNING clause captures the…
SQLite RETURNING Clause and Partial Cursor Consumption The SQLite RETURNING clause, introduced to provide PostgreSQL-like functionality for returning modified rows after INSERT, UPDATE, or DELETE operations, exhibits a unique behavior that can catch developers off-guard. Specifically, the RETURNING clause requires explicit consumption of the resulting cursor to ensure that all modifications are applied. This behavior…
Filtering Data by Time in SQLite Without a Timestamp Column When working with SQLite, one of the most common tasks is filtering data based on time. However, this task can become complicated if the database schema does not include a timestamp column. The core issue arises when users attempt to filter data from the last…
Non-Standard Date Formats Hindering Chronological Comparisons The core issue revolves around the inability to perform accurate date range queries in SQLite due to the use of non-standard date formats stored in the database. The specific problem arises when attempting to query records between two dates using the BETWEEN operator. The query fails to return the…
SQLite RETURNING Clause Cannot Be Used as a Subquery The SQLite RETURNING clause, introduced in version 3.35.0, allows users to retrieve the results of an INSERT, UPDATE, or DELETE statement directly within the same query. This feature is particularly useful for obtaining the values of newly inserted or modified rows without requiring a subsequent SELECT…
SQLite PENDING_BYTE and Locking Behavior in Sub-1GB Databases The SQLite database engine employs a sophisticated locking mechanism to ensure data integrity and concurrency control. One of the key components of this mechanism is the PENDING_BYTE, which is a byte used for setting PENDING locks. The PENDING_BYTE is typically located at the 0x40000000 (1 GB) offset…
Understanding RETURNING Clause Behavior in INSERT with ON CONFLICT The RETURNING clause in SQLite is a powerful feature that allows developers to retrieve the results of an INSERT, UPDATE, or DELETE operation directly within the same statement. This can be particularly useful when you need to immediately access the rowid or other columns of the…