我正在尝试使用 pypyodbc 将一些数据行插入到 SQL Server 数据库中。我编写的代码会捕获任何 pypyodbc.Error,如果发生这种情况,最多重试数据库操作 3 次。在我的测试中,我设法插入重复的关键数据行——异常被捕获并开始重试。问题是重试时没有捕获到异常并且代码挂起。这是代码:
# attempt to connect to the db - if unsuccessful, try up to 3 times
for i in range (3):
try:
# connect to db
db = pypyodbc.connect("DRIVER={SQL Server};SERVER=SERVER;DATABASE=DB;UID=user;PWD=password")
cursor = db.cursor()
# Loop round assigning the values in the lists at the given index to a new variable
for j in range (0,sector):
value1 = list1[j]
value2 = list2[j]
value3 = list3[j]
# print each of the values, as a sanity check
print('Value 1 = ' + value1)
print('Value 2 = ' + value2)
print('Value 3 = ' + value3+ "\n")
#if (value1 is not None and value2 is not None and value3 is not None):
cursor.execute('''INSERT INTO table(field1,field2,field3) VALUES (?,?,?)''', (value1,value2,value3))
cursor.commit()
# close off the open connections
cursor.close()
db.close()
# if successful, break out of the loop so there is no retry
break
# if there is a mysql exception thrown, print a message and retry
except pypyodbc.Error, e:
message = "Connection attempt " + str(i+1) + ": " + str(e)
print(message)
# if we reach this stage for a 3rd time, exit the program as no connection is possible and send an error email
if i == 2:
message = message + "\nThe script will now terminate."
print (message)
send_error_email(message)
sys.exit()
在第一次尝试时,值被写入控制台和异常(u'23000', u"[23000] [Microsoft][ODBC SQL Server Driver][SQL Server]Cannot insert duplicate key row in object....)报了。重试开始了,值再次写入控制台。这是程序挂起的地方。为什么重试时没有捕获到异常?