Question

我正在使用postgresql。在它上面我有我必须在python上使用的数据。一个表字段包含日期。它看起来像这样：

在我的python脚本上使用psycopg2我正在制作结果，当我得到日期时，它会在mongodb上保存为字符串

"created" : "2016-06-16T19:53:43.776456"

我的代码如下所示：

query = "SELECT name, created FROM user;"
cur.execute(query)
user_data = cur.fetchall()
for user_info in user_data:
    user_json = {
       'name': user_info[0],
       'created': user_info[1]
    }

我想将此"created" : "2016-06-16T19:53:43.776456"转换为"created" : ISODate("2016-06-24T09:08:09.333Z")，但我不知道如何以正确的格式转换它。请帮忙！

Answer 1

IMO在将数据存储到MongoDB时无需指定ISODate。

Python代码（片段）：

cur.execute("select name, created from tt_user;")
data = cur.fetchall()
for row in data:
    print(row[0], row[1])
    mdr = {
        'user': row[0],
        'created': row[1]
    }
    mongo_db.tt_user.insert_one(mdr)
print("Done.")

print("Check data in MongoDB");

for row in mongo_db.tt_user.find():
    print(row)

及其输出：

Load data from PostgreSQL into MongoDB...
('user1', datetime.datetime(2016, 6, 29, 13, 26, 28, 632436, tzinfo=psycopg2.tz.FixedOffsetTimezone(offset=180, name=None)))
('user2', datetime.datetime(2016, 6, 29, 13, 26, 28, 632739, tzinfo=psycopg2.tz.FixedOffsetTimezone(offset=180, name=None)))
('user3', datetime.datetime(2016, 6, 29, 13, 26, 28, 632751, tzinfo=psycopg2.tz.FixedOffsetTimezone(offset=180, name=None)))
('user4', datetime.datetime(2016, 6, 29, 13, 26, 28, 632757, tzinfo=psycopg2.tz.FixedOffsetTimezone(offset=180, name=None)))
('user5', datetime.datetime(2016, 6, 29, 13, 26, 28, 632762, tzinfo=psycopg2.tz.FixedOffsetTimezone(offset=180, name=None)))
Done.
Check data in MongoDB....
{u'_id': ObjectId('5773a254afd34b43d76aa792'), u'user': u'user1', u'created': datetime.datetime(2016, 6, 29, 10, 26, 28, 632000)}
{u'_id': ObjectId('5773a255afd34b43d76aa793'), u'user': u'user2', u'created': datetime.datetime(2016, 6, 29, 10, 26, 28, 632000)}
{u'_id': ObjectId('5773a255afd34b43d76aa794'), u'user': u'user3', u'created': datetime.datetime(2016, 6, 29, 10, 26, 28, 632000)}
{u'_id': ObjectId('5773a255afd34b43d76aa795'), u'user': u'user4', u'created': datetime.datetime(2016, 6, 29, 10, 26, 28, 632000)}
{u'_id': ObjectId('5773a255afd34b43d76aa796'), u'user': u'user5', u'created': datetime.datetime(2016, 6, 29, 10, 26, 28, 632000)}

在MongoDB控制台中：

> db.tt_user.find()
{ "_id" : ObjectId("5773a254afd34b43d76aa792"), "user" : "user1", "created" : ISODate("2016-06-29T10:26:28.632Z") }
{ "_id" : ObjectId("5773a255afd34b43d76aa793"), "user" : "user2", "created" : ISODate("2016-06-29T10:26:28.632Z") }
{ "_id" : ObjectId("5773a255afd34b43d76aa794"), "user" : "user3", "created" : ISODate("2016-06-29T10:26:28.632Z") }
{ "_id" : ObjectId("5773a255afd34b43d76aa795"), "user" : "user4", "created" : ISODate("2016-06-29T10:26:28.632Z") }
{ "_id" : ObjectId("5773a255afd34b43d76aa796"), "user" : "user5", "created" : ISODate("2016-06-29T10:26:28.632Z") }
>

所以这是客户端软件的行为，而不是存储问题。只需将数据保存为日期时间。

PS：谢谢你强迫我最后安装MongoDB：）

Answer 2

替换此

query = "SELECT name, created FROM user;"

由此

query = "SELECT name, 'ISODate(\"' || created || '\")' FROM user;"

查询将返回您要存储为created的格式良好的字符串。

将字符串转换为ISO日期python

2 个答案: