I recently had a task where a UITableView should suggest autocomplete for a word I started to type into a UISearchBar/Search Display Controller.
From the top of my head I came up with the SQL query that I wanted to use:
SELECT string FROM table WHERE string LIKE 'S%';
This query should return all the strings that start with capital S.
For a NSPredicate the query has to look like this:
NSString *query = [NSString stringWithFormat:@"String LIKE '%@%%'", startOfString];
Most important here is that the percent sign needs to be escaped with another percent sign (%%).