Syntax error: SQL INSERT from Python + Scrapy?

Create a web scraper in Python 2.6.4 + Scrapy. Need data analysis, but also my first Python learning project. Failed to create SQL INSERT statement in my pipe.py article. A real query contains approximately 30 attributes to insert.

First, is there a better way to write this UPDATE or INSERT algorithm? Discover for improvement.

Secondly, there are two different syntax options and various errors that they create. I tried a lot of example-based options, but I can't find an example using the "INSERT SET", which breaks into several lines. What is the correct syntax?

The DB is empty, so we always fork to the INSERT block.

def _conditional_insert(self, tx, item):
 # create record if doesn't exist.
 tx.execute("SELECT username  FROM profiles_flat WHERE username = %s", (item['username'][0], ))
 result = tx.fetchone()

 if result:
    # do row UPDATE
     tx.execute( \
        """UPDATE profiles_flat SET
        username=`%s`, 
        headline=`%s`,
        age=`%s`
        WHERE username=`%s`""", (  \
        item['username'],
        item['headline'],
        item['age'],)
        item['username'],)
     )         
 else: 
   # do row INSERT
   tx.execute( \
   """INSERT INTO profiles_flat SET
        username=`%s`, 
        headline=`%s`,
        age=`%s` """, ( \
        item['username'],
        item['headline'],
        item['age'], )   # line 222
   )

Error:

[Failure instance: Traceback: <class '_mysql_exceptions.OperationalError'>: (1054, "Unknown column ''missLovely92 '' in 'field list'")
  /usr/lib/python2.6/threading.py:497:__bootstrap
  /usr/lib/python2.6/threading.py:525:__bootstrap_inner
  /usr/lib/python2.6/threading.py:477:run
  --- <exception caught here> ---
  /usr/lib/python2.6/vendor-packages/twisted/python/threadpool.py:210:_worker
  /usr/lib/python2.6/vendor-packages/twisted/python/context.py:59:callWithContext
  /usr/lib/python2.6/vendor-packages/twisted/python/context.py:37:callWithContext
  /usr/lib/python2.6/vendor-packages/twisted/enterprise/adbapi.py:429:_runInteraction
  /export/home/raven/scrapy/project/project/pipelines.py:222:_conditional_insert
  /usr/lib/python2.6/vendor-packages/MySQLdb/cursors.py:166:execute
  /usr/lib/python2.6/vendor-packages/MySQLdb/connections.py:35:defaulterrorhandler
  ]

Alternative syntax:

  query = """INSERT INTO profiles_flat SET
        username=`%s`, 
        headline=`%s`,
        age=`%s` """ % \
   item['username'], # line 196
   item['headline'],
   item['age']

   tx.execute(query)

Error:

  [Failure instance: Traceback: <type 'exceptions.TypeError'>: not enough arguments for format string
  /usr/lib/python2.6/threading.py:497:__bootstrap
  /usr/lib/python2.6/threading.py:525:__bootstrap_inner
  /usr/lib/python2.6/threading.py:477:run
  --- <exception caught here> ---
  /usr/lib/python2.6/vendor-packages/twisted/python/threadpool.py:210:_worker
  /usr/lib/python2.6/vendor-packages/twisted/python/context.py:59:callWithContext
  /usr/lib/python2.6/vendor-packages/twisted/python/context.py:37:callWithContext
  /usr/lib/python2.6/vendor-packages/twisted/enterprise/adbapi.py:429:_runInteraction
  /export/home/raven/scrapy/project/project/pipelines.py:196:_conditional_insert
  ]