How to add a current string into an already existing list

[Nick the Gr33k]

Στις 5/11/2013 12:46 πμ, ο/η Denis McMahon έγραψε:
> On Mon, 04 Nov 2013 19:03:58 +0200, Nick the Gr33k wrote:

> There is no built in support in the python / mysql system for puttinga
> list straight into a database, because mysql does not have"collection"
> record type.

Does postgresql has this 'collection' record type


> You could convert the python list into a storable entity, for example
> imploding a list of strings with some arbitrary separator to create a
> long string, store the long string, then when you read it from the
> database explode it back into a list.
> Which method you use is up to you. There may be others.
> Pick a method and code it.

Okey here is my attempt to code your solution as best as i can get my 
head around it:

This is the part that is responsible to do the database insertion 
converting scalars to lists and backwards.

=====================================
	try:
		# if first time for webpage; create new record( primary key is 
automatic, hit is defaulted ), if page exists then update record
		cur.execute('''INSERT INTO counters (url) VALUES (%s) ON DUPLICATE KEY 
UPDATE hits = hits + 1''', page )
		cID = cur.lastrowid

		# fetch those columns that act as lists but are stored as strings
		cur.execute('''SELECT refs, visits, downloads FROM visitors WHERE 
counterID = %s''', cID )
		data = cur.fetchone

		ref = data[0]
		visit = data[1]
		download = data[2]
		
		# retrieve long strings and convert them into lists respectively
		refs = ref.split()
		visits = visit.split()
		downloads = download.split()
		
		# add current strings to the each list respectively
		refs.appends( ref )
		visits.appends( visit )
		downloads.appends( download )
		
		# convert lists back to longstrings
		refs = ', '.join( refs )
		visits = ', '.join( visits )
		downloads = ', '.join( downloads )

		# add this visitor entry into database (hits && downloads are defaulted)
		cur.execute('''INSERT INTO visitors (counterID, refs, host, city, 
useros, browser, visits, hits = hits + 1, downloads) VALUES (%s, %s, %s, 
%s, %s, %s, %s, %s, %s)''',
						(cID, refs, host, city, useros, browser, visits, hits, downloads) )

		con.commit()
	except pymysql.ProgrammingError as e:
		print( repr(e) )
		con.rollback()
		sys.exit(0)
===================================

Please tell me if this logic is correct, for some reason it doesn't do 
what i need it to do.

Thank you.