connect to sample user db2admin using       

   Database Connection Information

 Database server        = DB2/NT  8 . 1 . 3 
 SQL authorization ID   = DB2ADMIN
 Local database alias   = SAMPLE


create table ttt1 ( id integer, name char( 35 ) )
DB20000I  The SQL command completed successfully.

create unique index ittt1 on ttt1 (id)
DB20000I  The SQL command completed successfully.

insert into ttt1 (id,name) values (NULL,'qweqwe')
DB20000I  The SQL command completed successfully.

insert into ttt1 (id,name) values (NULL,'qweqerwerwe')
DB21034E  The command was processed as an SQL statement because it was not a 
valid Command Line Processor command.  During SQL processing it returned:
SQL0803N  One or more values in the INSERT statement, UPDATE statement, or 
foreign key update caused by a DELETE statement are not valid because the 
primary key, unique constraint or unique index identified by  "1 " constrains 
table  "DB2ADMIN.TTT1"  from having duplicate rows for those columns.  
SQLSTATE= 23505 

insert into ttt1 (id,name) values (NULL,'qweqwerwerwe')
DB21034E  The command was processed as an SQL statement because it was not a 
valid Command Line Processor command.  During SQL processing it returned:
SQL0803N  One or more values in the INSERT statement, UPDATE statement, or 
foreign key update caused by a DELETE statement are not valid because the 
primary key, unique constraint or unique index identified by  "1 " constrains 
table  "DB2ADMIN.TTT1"  from having duplicate rows for those columns.  
SQLSTATE= 23505 

create table ttt1 (
	id integer,
	name char( 35 )
)

create unique index ittt1 on ttt1(id)

insert into ttt1 (id,name) values (NULL,'1111')
insert into ttt1 (id,name) values (NULL,'34531111')

Server Message:  Number   2601 , Severity   14 
Server 'pnsybase', Line  1 :
Attempt to insert duplicate key row in object 'ttt1' with unique index 'ittt1' 
Server Message:  Number   3621 , Severity   10 
Server 'pnsybase', Line  1 :
Command has been aborted.