Question

I get an Integrity constraint violation by a delete sql statement. This happens because the id of a table is used in another table as Primary Key. However I want to delete them anyway, by using CASCADE.

But what’s the correct syntax for hsqldb?

Answer 1

The DELETE statement does not support a “cascade” keyword (which is clearly documented in the manual)

You need to setup the foreign key constraint to cascade deletes:

create table playlist
(
   id integer primary key not null, 
   ... other columns ...
);

create table playlistmovies
(
   id integer primary key not null,
   playlist_id integer not null,
   ... other columns
);

alter table playlistmovies
   add constraint fk_plm_playlist
   foreign key (playlist_id) references playlist(id)
   on delete cascade;

Then when you delete a playlist, all rows referencing that playlist are also deleted.