Viewing file:  converters.py (1.31 KB) -rw-r--r--
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import os
import sqlite
# Ok, let's define a user-defined type we can use with the SQLite database
class Point:
def __init__(self, x, y):
self.x, self.y = x, y
# The _quote function is currently the way a PySQLite user-defined type
# returns its string representation to write to the database.
def _quote(self):
return "'%f,%f'" % (self.x, self.y)
def __str__(self):
return "Point(%f, %f)" % (self.x, self.y)
# The conversion callable needs to accept a string, parse it and return an
# instance of your user-defined type.
def pointConverter(s):
x, y = s.split(",")
return Point(float(x), float(y))
# Ensure we have an empty database
if os.path.exists("db"): os.remove("db")
cx = sqlite.connect("db", converters={"point": pointConverter})
cu = cx.cursor()
cu.execute("create table test(p point, n int)")
cu.execute("insert into test(p, n) values (%s, %s)", (Point(-3.2, 4.5), 25))
# For user-defined types, and for statements which return anything but direct
# columns, you need to use the "-- types" feature of PySQLite:
cu.execute("-- types point, int")
cu.execute("select p, n from test")
row = cu.fetchone()
print "p:", row.p # .columnname instead of [0] is a PySQLite
print "n:", row.n # extension to the DB-API!
cx.close()
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