def load_by_parameter(brand):
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
# ? placeholder
# the real parameter expects a tuple or list, so we have to wrap it
# into tuple
# even there is just only one element
cursor = conn.execute("SELECT Id,Brand,Model,Price FROM Cars WHERE Brand=?",(brand,))
Car.display(cursor2cars(cursor))
# named placeholder
cursor = conn.execute("SELECT COUNT(*) AS Count,AVG(Price) FROM Cars WHERE Brand=:brand",{"brand":brand})
# we know the result is only one row, so we can call fetchone()
row = cursor.fetchone()
print "'{brand}' has {total} cars, average price is {avgprice:.3f}".format(brand=brand,total=row[0],avgprice=row[1])
def load_access_col_by_name():
"""
to access each column in row by name instead of index
we need to set connection's row_factory to 'sqlite3.Row'
"""
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
conn.row_factory = sqlite3.Row
cursor = conn.execute("SELECT * FROM Cars")
cars = []
for row in cursor:
c = Car(brand=row["Brand"],price=row["Price"],model=row["Model"])
c.id = row["Id"]
cars.append(c)
Car.display(cars)
def load_access_col_by_name():
"""
to access each column in row by name instead of index
we need to set connection's row_factory to 'sqlite3.Row'
"""
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
conn.row_factory = sqlite3.Row
cursor = conn.execute("SELECT * FROM Cars")
cars = []
for row in cursor:
c = Car(brand=row["Brand"], price=row["Price"], model=row["Model"])
c.id = row["Id"]
cars.append(c)
Car.display(cars)
def load_by_parameter(brand):
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
# ? placeholder
# the real parameter expects a tuple or list, so we have to wrap it
# into tuple
# even there is just only one element
cursor = conn.execute(
"SELECT Id,Brand,Model,Price FROM Cars WHERE Brand=?", (brand, ))
Car.display(cursor2cars(cursor))
# named placeholder
cursor = conn.execute(
"SELECT COUNT(*) AS Count,AVG(Price) FROM Cars WHERE Brand=:brand",
{"brand": brand})
# we know the result is only one row, so we can call fetchone()
row = cursor.fetchone()
print "'{brand}' has {total} cars, average price is {avgprice:.3f}".format(
brand=brand, total=row[0], avgprice=row[1])
def load_basic():
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
cursor = conn.execute("SELECT Id,Brand,Model,Price FROM Cars ORDER BY PRICE")
Car.display(cursor2cars(cursor))
def load_basic():
with sqlite3.connect(Database) as conn:
conn.text_factory = str # by default, it will return unicode, so change it to 'str'
cursor = conn.execute(
"SELECT Id,Brand,Model,Price FROM Cars ORDER BY PRICE")
Car.display(cursor2cars(cursor))