The serial datatype creates a sequence in the background. So, in your example, you'll have a sequence called "student_id_seq". Your sequence was probably reset, dropped/created, or whatever, to cause it to feed IDs back that already exist in your table.
On July 2, 2004 10:22 am, [EMAIL PROTECTED] wrote: > Hello > i have: > create table student( > id SERIAL NOT NULL, > name VARCHAR(35) NOT NULL, > primary key (id) > ); > > and when i try to insert like this: > insert into student (name) values('me'); > i receive error: > ERROR: duplicate key violates unique constraint "student_pkey" > > Why ? Do i understeand correctly that SERIAL == AUTO_INCREMENT ? > As far as i remember i used such type in the past and had no problem. > What do i miss ? > > Thanx > Michal > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend -- Michael A. Nachbaur <[EMAIL PROTECTED]> http://nachbaur.com/pgpkey.asc ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match