Hi,
I'm on XP Pro using PythonWin, but I use a remote virtual unix machine on a server somewhere to run scripts. Using Python 2.5, MySQL 5.0
The problem is that I have a need to regularly query several MySQL databases on different machines to do my analysis. So I decided to try and organise myself a bit better and have some class structure with common code in appropriate levels of it.
I have set the top class to default to the database I use most often. But I wanted the derived classes to overwrite the host, port and db. Nothing I try seems to work. Obviously I am too old and need to be taken outside and shot. Alternatively somebody could point out the error of my ways I would be eternaly grateful. PS I can't spell either.
So I have a top class MySQLconnection as follows.
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import sys
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import MySQLdb
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class MySQLconnection:
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def __init__ (self, username, password):
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self.username=username
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self.password=password
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self.host_details=abc.def.ghi.com'
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self.port_number=1234
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self.db_name='lots_of+things'
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self.sslparms = { 'something': '/dev/null' }
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self.db = MySQLdb.connect(
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host=self.host_details,
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port=self.port_number,
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user=self.username,
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passwd=self.password,
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db=self.db_name)
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self.cursor = self.db.cursor()
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def single_result(self):
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row = self.cursor.fetchone()
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if row is not None:
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return row[0]
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def array_result(self):
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rows = self.cursor.fetchall()
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if rows is not None:
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return [row[0] for row in rows]
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def result(self):
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return self.cursor.fetchall()
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and a dervided class for each Database as follows
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mport sys
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import MySQLdb
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import MySQLconnection
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class StatsConnection(MySQLconnection.MySQLconnection):
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self.host_details='some other database'
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self.port_number=1236
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self.db_name='other_things'
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self.sslparms = { 'qwerty': '/dev/null' }
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def some database specifc methods etc etc
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Then an example query becomes
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import sys
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import StatsConnection
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username="TopSecret"
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password="ExtremelyTopSecret"
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stats=StatsConnection.StatsConnection(username, password)
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def select_thing():
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stats.cursor.execute("""select e.thing from
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database.tbl_things as e limit 1""")
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return stats.single_result()
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x=select_rs()
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print x
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obviously the self is wrong in the derived class. What I am trying to do is have the derived class overwrite the specifics for the database connection it represnts.
