Thread: [GENERAL] DROP INDEX CASCADE doesn't want to drop unique constraints?

[GENERAL] DROP INDEX CASCADE doesn't want to drop unique constraints?

From
Ivan Voras
Date:
Hello,

On trying to drop an index named "employer_employerid_key" which supports a unique constraint:

    "employer_employerid_key" UNIQUE CONSTRAINT, btree (employerid)

I get this error:

ERROR:  cannot drop index employer_employerid_key because constraint employer_employerid_key on table employer requires it
HINT:  You can drop constraint employer_employerid_key on table employer instead.

I'm using the CASCADE and IF EXISTS arguments and the docs say nothing about any special cases (https://www.postgresql.org/docs/9.3/static/sql-dropindex.html). This is with PostgreSQL 9.3.15. 

The actual command is:

drop index if exists employer_employerid_key cascade;

Any ideas if this is normal or why it happens?



Re: [GENERAL] DROP INDEX CASCADE doesn't want to drop uniqueconstraints?

From
Andreas Kretschmer
Date:
Ivan Voras <ivoras@gmail.com> wrote:

> Hello,
>
> On trying to drop an index named "employer_employerid_key" which supports a
> unique constraint:
>
>     "employer_employerid_key" UNIQUE CONSTRAINT, btree (employerid)
>
> I get this error:
>
> ERROR:  cannot drop index employer_employerid_key because constraint
> employer_employerid_key on table employer requires it
> HINT:  You can drop constraint employer_employerid_key on table employer
> instead.
>
> I'm using the CASCADE and IF EXISTS arguments and the docs say nothing about
> any special cases (https://www.postgresql.org/docs/9.3/static/
> sql-dropindex.html). This is with PostgreSQL 9.3.15. 
>
> The actual command is:
>
> drop index if exists employer_employerid_key cascade;
>
> Any ideas if this is normal or why it happens?


Drop the constraint:

alter table employer drop constraint employer_employerid_key;





Regards, Andreas Kretschmer
--
Andreas Kretschmer
http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services