Using sqlite with Firefox sqlite-manager extension

The Stanford database course is using sqlite to experiment with SQL, Constraints, Triggers and so on. As the downloadable executable from this site only has a command line interface I decided to search for a GUI manager for sqlite. I am currently trying the firefox add-on which seems to work just fine.

/* First we create a table with a tuple constraint */
create table Apply(sID int, cName text, major text, decision text, 
check(decision = 'N' or cName <> 'Stanford' or major <> 'CS'));

/* next we try to insert a few tuples but the 3rd one should throw a constraint violation exception */
insert into Apply values(123, 'Stanford', 'CS', 'N');
insert into Apply values(123, 'MIT', 'CS', 'Y');
insert into Apply values(123, 'Stanford', 'CS', 'Y');