probleme dropping constraint

Hi Informixers, I want to start with the constraint instruction between tabels and columns. I created a constraint with: alter table t_lev modify(lev_nr char(10) primary key); alter table t_dgbaah add constraint (foreign key (dah_derde) referencest_lev(lev_nr); After this I can't remove any record anymore out of table t_lev where the lev_nr still exists in the column dah_derde of the table t_dgbaah. So far so good. But, if I want to remove the constraint, I use the instruction: alter table t_dgbaah drop constraint dah_derde; Then the system answers: 623: Unable to find CONSTRAINT (dah_derde). What's going wrong?? Thanks for any help. Danny ddk@fidelity-soft.be

The constraint will not be named dah_derde. Since you did not explicitly name the constraint. Informix made one up for you. Look at a dbschema for table t_dgbaah. On the alter table after the table name in the references clause , it will say constraint "owner".constraint_name. You need to use that constraint name to drop it. Danny De Koster wrote: > > Hi Informixers, > > I want to start with the constraint instruction between tabels and columns. > I created a constraint with: > > alter table t_lev modify(lev_nr char(10) primary key); > alter table t_dgbaah add constraint (foreign key (dah_derde) references> t_lev(lev_nr); > > After this I can't remove any record anymore out of table t_lev where the > lev_nr still exists in the column dah_derde of the table t_dgbaah. So far so > good. > But, if I want to remove the constraint, I use the instruction: > > alter table t_dgbaah drop constraint dah_derde;> > Then the system answers: 623: Unable to find CONSTRAINT (dah_derde). > > What's going wrong?? > > Thanks for any help. > > Danny > ddk@fidelity-soft.be

Danny De Koster wrote: > I want to start with the constraint instruction between tabels and columns. > I created a constraint with: > > alter table t_lev modify(lev_nr char(10) primary key); > alter table t_dgbaah add constraint (foreign key (dah_derde) references> t_lev(lev_nr); > > After this I can't remove any record anymore out of table t_lev where the > lev_nr still exists in the column dah_derde of the table t_dgbaah. So far so > good. But, if I want to remove the constraint, I use the instruction: > > alter table t_dgbaah drop constraint dah_derde;> > Then the system answers: 623: Unable to find CONSTRAINT (dah_derde). > What's going wrong?? You didn't specify the name of the constraint, so it has a system manufactured name, and that manufactured name is not dah_derde. You will need to find the correct constraint name (possibly via DB-Access), and then drop it. It the constraint name has a leading blank, then you will need to (a) set DELIMIDENT=yes in the environment and (b) specify the constraint name inside double-quotes in the ALTER TABLE statement. -- Yours, Jonathan Leffler (Jonathan.Leffler@Informix.com) #include <disclaimer.h> Guardian of DBD::Informix v1.00.PC1 -- http://www.perl.com/CPAN "I don't suffer from insanity; I enjoy every minute of it!"