Question

The database I am working on was originally prototyped (by someone else) with all the primary keys (and associated foreign keys) as strings. The keys really need to be numeric.

The database has 16 tables with minimal test data in it. All the data has numbers in the key fields.

What is the easiest way for me to fix this?

Answer 1

I created a SQL script to make the change on a single association then I’ll modify and repeat it 20 more times.

I did the first table (MODULES.ID to MODULE_SESSIONS.MODULE_ID association) and it worked.
Here is the script I used:

alter table MODULE_SESSIONS drop constraint FK_MODULE_MODULE_SESSION_FK1;
alter table MODULES drop constraint MODULES_PK;
alter table MODULES rename column ID to OLD;
alter table MODULES add ID INTEGER;
update MODULES set ID = OLD;
alter table MODULES drop column OLD;
alter table MODULE_SESSIONS rename column MODULE_ID to OLD;
alter table MODULE_SESSIONS add MODULE_ID INTEGER;
update MODULE_SESSIONS set MODULE_ID = OLD;
alter table MODULES add constraint MODULE_PK primary key(ID); 
alter table MODULE_SESSIONS add constraint FK_MODULE_MODULE_SESSION_FK1 foreign key(MODULE_ID) references MODULES(ID);
alter table MODULE_SESSIONS drop column OLD;