Question

Given a database field named ‘widget_ids’, containing data like ’67/797/124/’ or ’45/’, where the numbers are slash separated widget_ids… how would you make an update statement with SQL that would say: ‘if the widget_ids of the row with id X contains the text ‘somenumber/’ do nothing, otherwise append ‘somenumber/’ to it’s current value’

Can you do something like that with SQL, or more specifically, sqlite? Is that something that is better done in the program for some reason or is there support for ‘if-then’ like syntax in SQL?

Answer 1

Updates are kind of like if-thens themselves, and there is also if-then support of some sort in most SQL implementations. A simple solution might be:

update <tablename>   set widget_id = widget_id + 'somenumber/'   where row_id = X     and widget_id not like '%/somenumber/%'     and widget_id not like 'somenumber/%';