If you are more interested in the ones that are not unique, I use Select col_name,count(*) From table Group by col_name Having count(*) > 1 Kind regards, Eric -----Oorspronkelijk bericht----- Van: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] Namens Chirag DBA Verzonden: woensdag 18 mei 2005 8:31Aan: jacintakean@xxxxxxxxx CC: oracle-l@xxxxxxxxxxxxx Onderwerp: Re: Uniqueness If it is a primary key, it will be unique... if not then you have to write an sql for finding duplicate values. If there are duplicate values it is not unique. select col_name from table1 where rowid not in(Select min(rowid) from table1 group by col1,col2,col3,....); Hope this will work. Regards - Chirag=20 On 5/18/05, Kean Jacinta <jacintakean@xxxxxxxxx> wrote: > Hi again, >=20 > Is there a way to check for uniqueness of a value ? > Apart from set the column to be unique ? >=20 > For example : >=20 > Table : mytbl > PK ID > ---- > 1 > 2 > 3 >=20 > Insert into mytbl (id) values (2); >=20 > Oracle will give error. >=20 >=20 > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around >http://mail.yahoo.com > -- > //www.freelists.org/webpage/oracle-l > -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l