Generic SQL Engine
SQLite virtual tables allow a developer to define the contents of a table through code. By defining a set of callback functions that fetch and return rows and columns, a developer can create a link between the SQLite data processing engine and any data source. This allows SQLite to run queries against the data source without importing the data into a standard table.
Virtual tables are an extremely useful way to generate reports or allow ad hoc queries against logs or any tabular data set. Rather than writing a set of custom search or reporting tools, the data can simply be exposed to the SQLite engine. This allows reports and queries to be expressed in SQL, a language that many developers are already familiar with using. It also enables the use of generic database visualization tools and report generators.
Chapter 10 shows how to build a virtual table module that provides direct access to live web server logs.
Get Using SQLite now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
