Question

我正在使用pyodbc从MSQL Server获取一些数据。工作正常，除了检索大量数据时：它真的很慢。

我有大约4000行，这不是一个非常大的数字。

conn = pyodbc.connect('DRIVER={SQL Server};SERVER=192.168.1.10;DATABASE=MyDB;Trusted_Connection=yes;')
cur = conn.cursor()
cur.execute('SELECT * FROM myTable')

我尝试了以下内容：

time1 = datetime.datetime.now()
a = cur.fetchall()
time2 = datetime.datetime.now()
print time2 - time1
print len(a)

0：00：27.286000

time1 = datetime.datetime.now()
for i in range(0, 4017):
    cur.fetchone()
time2 = datetime.datetime.now()
print time2 - time1

0：00：21.196000

time1 = datetime.datetime.now()
allIDRows = list(cur.fetchmany(4017))
time2 = datetime.datetime.now()
print time2 - time1

0：00：23.845000

time1 = datetime.datetime.now()
a = cur.fetchmany(4017)
time2 = datetime.datetime.now()
print time2 - time1

0：00：24.348000

def ResultIter(cursor, arraysize=100):
    'An iterator that uses fetchmany to keep memory usage down'
    while True:
        results = cursor.fetchmany(arraysize)
        if not results:
            break
        for result in results:
            yield result
time1 = datetime.datetime.now()
for result in ResultIter(cur):
    pass
time2 = datetime.datetime.now()
print time2 - time1

0：00：31.181000

知道为什么它如此缓慢以及我应该做些什么才能让它变得快速？（好吧，如果有可能......）

由于

Python pyodbc fetch很慢

0 个答案: