psql postgres gives err: psql; FATAL: role "root" does not exist. (as root) psql; FATAL: role "user" does not exist. (as user)
If you do not specify the -U switch(user) for psql it will use the system user that you are logged in as. If that user does not have a Postgres role then you get the above. To avoid the above and get the behavior you are getting with sudo, do the following as any system user:
By the way the -d postgres means you are connecting to one of the Postgres 'system' databases. That is not really where you want to create objects. I would suggest creating you own database in the cluster for doing your work.
> > > But if I use Python with psycopg2 > ----- > import psycopg2 > > conn=psycopg2.connect(host='localhost',database='postgres',user='postgres',password='postgres') > cur=conn.cursor() > > retval = cur.callproc('personnelinsert',[34567,'Galilei, Galileo']) > > conn.commit() > > cur.close() > conn.close() > > print(retval) > ----- > retval = [34567,'Galilei, Galileo'] > (I'm expecting retval/serialid value of 3, not the parameters I sent) > > > Q1: From Python, is there a way I can retrieve the value of > "retval/serialid" of my UDF?
Return values from Postgres functions are just like other expression values. The most straightforward way to retrieve your function's return value would be something like this:
