How to add a current string into an already existing list

[Nick the Gr33k]

Στις 5/11/2013 8:54 πμ, ο/η Nick the Gr33k έγραψε:
> 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.


Better version for it, i think, but still none working:

=========================================
		# 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 = (SELECT ID FROM counters WHERE url = %s) ORDER BY visits 
DESC''', page )
		data = cur.fetchall

		for row in data:
			(refs, visits, downloads) = row
		
			# retrieve long strings and convert them into lists respectively
			refs = ref.split()
			visits = visit.split()
			downloads = download.split()
		
			# add current strings to 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) )
=========================================

[Tue Nov 05 10:06:57 2013] [error] [client 176.92.96.218] Traceback 
(most recent call last):
[Tue Nov 05 10:06:57 2013] [error] [client 176.92.96.218]   File 
"/home/nikos/public_html/cgi-bin/metrites.py", line 267, in <module>
[Tue Nov 05 10:06:57 2013] [error] [client 176.92.96.218]     for row in 
data:
[Tue Nov 05 10:06:57 2013] [error] [client 176.92.96.218] TypeError: 
'method' object is not iterable

How is ti possible for data to be none iterable?