python将字符串时间转换为sql日期时间格式

我正在将一个大型csv文件导入ETL到数据库中，最初在csv文件中设置的日期格式看起来像

4/22/2016 1:00:00 PM

。每个日期都是较大列表的一部分，其中可能包含非日期类型的项。例如：

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

我想用正确的MySQL格式重新格式化每个日期（如果列表中有）

%m-%d-%Y%I:%m:%S

我如何使用列表理解来实现这一点？我的代码不起作用的原因很明显，但我不确定从这里走到哪里。我需要保留在

v

中找到日期的索引

from datetime import datetime, date, time

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]


def fixdate(_params):
        tstamp = datetime.strptime(_params, "%m/%d/%Y %I:%M:%S %p")
        newtstamp = date.strftime(tstamp, "%m-%d-%Y %I:%M:%S")
        replace = { _params: newtstamp }
        l = [replace.get(x, x) for x in _params]
        print l


fixdate(v)

---

请检查这个注释与代码内联。

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params
        #First date in list
        tstamp = datetime.strptime(_params[0], "%m/%d/%Y %I:%M:%S %p")
        #Add %p after %S if AM or PM is required
        newtstamp = datetime.strftime(tstamp, "%m-%d-%Y %I:%M:%S")
        #Update the element in list
        _params[0] = newtstamp

        #Second date in list
        tstamp = datetime.strptime(_params[1], "%m/%d/%Y %I:%M:%S %p")
        newtstamp = datetime.strftime(tstamp, "%m-%d-%Y %I:%M:%S")
        #Update the element in list
        _params[1] = newtstamp

        print "After changing format..."
        print _params

fixdate(v)

输出：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

具有列表理解功能的代码：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

输出：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

---

请检查这个注释与代码内联。

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params
        #First date in list
        tstamp = datetime.strptime(_params[0], "%m/%d/%Y %I:%M:%S %p")
        #Add %p after %S if AM or PM is required
        newtstamp = datetime.strftime(tstamp, "%m-%d-%Y %I:%M:%S")
        #Update the element in list
        _params[0] = newtstamp

        #Second date in list
        tstamp = datetime.strptime(_params[1], "%m/%d/%Y %I:%M:%S %p")
        newtstamp = datetime.strftime(tstamp, "%m-%d-%Y %I:%M:%S")
        #Update the element in list
        _params[1] = newtstamp

        print "After changing format..."
        print _params

fixdate(v)

输出：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

具有列表理解功能的代码：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

输出：

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

from datetime import datetime

v = ['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]

def fixdate(_params):

        print "Before changing format ..."
        print _params

        _params = [i if ':' not in str(i) and '/' not in str(i) else datetime.strftime(datetime.strptime(i, "%m/%d/%Y %I:%M:%S %p"), "%m-%d-%Y %I:%M:%S") for i in _params]

        print "After changing format..."
        print _params

fixdate(v)

C:\Users\dinesh_pundkar\Desktop>python c.py
Before changing format ...
['4/29/2016 8:25:58 AM', '5/25/2016 2:22:22 PM', 'True', 'Foo', 1]
After changing format...
['04-29-2016 08:25:58', '05-25-2016 02:22:22', 'True', 'Foo', 1]

C:\Users\dinesh_pundkar\Desktop>

---

@多布斯-请让我知道如果你想要任何其他信息。谢谢你的提交。我正在处理的实际列表要大得多（17个元素），如果可能的话，我希望通过列表理解来完成这一点，而不是指定需要修改的每个索引。我更新了上面的问题以解决this@dobbs-如果您需要任何其他信息，请告诉我。谢谢您的提交。我正在处理的实际列表要大得多（17个元素），如果可能的话，我希望通过列表理解来完成这一点，而不是指定需要修改的每个索引。为了解决这个问题，我更新了上面的问题