Now, pdocrud support invoice generation directly from database. A new invoice layout is added to support the generation of invoice easily. Currently it is in beta release. We will release full featured invoice generation in next version. Please check the comments of the code to understand how it works.
PDF generation helps you automate various tasks including automatic calculations of various totals, generation of pdf in various invoice format. You will need xInvoice - Generate beautifully designed invoices dynamically in order to generate invoice pdf. You need to put xinvoice script in the library folder.
Database used for this demo contains 5 tables. You can design the database as you want.