Can't drop table

Hi,

I have created a table called experimenters with the following query:

CREATE TABLE experimenters (     experimenter_id  INTEGER CONSTRAINT firstkey PRIMARY KEY,     first_name
CHAR(20),    last_name        CHAR(25),     address          CHAR(30),     phone_num        CHAR(15)
 
);

The query was successful. But when I try to drop or alter the table, it just hangs without echoing any error message. I
haveto cancel the query to get out.
 

I ran the following query to drop the table

DROP TABLE experimenters;

It also hangs when I try to alter the table.

Just don't understand the problem here.

Any help will be highly appreciated.

Thanks in advance

Hima