SQLite Tutorial

Data dodania: 2012-02-02, Autor: Mike Chirico, Dodał: Karol, Wyświetleń: 267

This article explores the power and simplicity of sqlite3, starting with common commands and triggers. It then covers the attach statement with the union operation, introduced in a way that allows multiple tables, in separate databases, to be combined as one virtual table, without the overhead of copying or moving data. Next, I demonstrate the simple sign function and the amazingly powerful trick of using this function in SQL select statements to solve complex queries with a single pass through the data, after making a brief mathematical case for how the sign function defines the absolute value and IF conditions.

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