: For operations involving multiple updates (e.g., marking an item as "rented" while creating a billing record), wrap the logic in a BEGIN TRANSACTION and COMMIT to maintain data integrity.
: Replace SELECT * with explicit column names. This reduces unnecessary data transfer and prevents issues if the table schema changes . wynajem.sql
: Use CREATE TABLE IF NOT EXISTS or DROP TABLE IF EXISTS to ensure the script can be run multiple times without errors. : For operations involving multiple updates (e
: Keywords should be in UPPERCASE (e.g., SELECT , FROM , WHERE ) to distinguish them from table and column names, which should follow a consistent snake_case or PascalCase naming convention. : Use CREATE TABLE IF NOT EXISTS or
: Add inline comments ( -- ) or block comments ( /* ... */ ) to explain complex logic, such as how tax is calculated or how "available" status is determined.
: Use explicit INNER JOIN or LEFT JOIN syntax rather than comma-separated tables in the WHERE clause for better readability and maintenance . 4. Safety & Transactions
: Verify that the rental data is normalized (e.g., separate tables for Klienci (Customers), Obiekty (Properties/Items), and Wynajmy (Rentals)). Ensure there is no redundant storage of rental rates in the transaction table if they can be retrieved via a JOIN from the primary item table .