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Issue 20.2 ('Colorominoes')
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Triggers and Orphans

A Brief Discussion on SQL

Issue: 20.2 (March/April 2022)
Author: Vince Du Beau
Author Bio: Vince is an experienced Filemaker developer. He is exploring XOJO as an alternative to Filemaker.
Article Description: No description available.
Article Length (in bytes): 3,915
Starting Page Number: 84
Article Number: 20209
Related Link(s): None

Excerpt of article text...

Triggers are used to initiate an action during certain database events such as an insert, update, or delete. They can be designed to occur either before or after the event.

Developers usually design them to work at the row level. They can also be specified to run based on a specific statement.

I worked on a project a few years back when using UUIDS (Universally Unique IDs) was all the rage in the Filemaker community for primary keys. I wanted to see if I could do it with SQLite. An example trigger to create a UUID when inserting a new customer record follows:



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