大约有 36,010 项符合查询结果（耗时：0.0474秒） [XML]
MongoDB - Update objects in a document's array (nested updating)
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For question #1, let's break it into two parts. First, increment any document that has "items.item_name" equal to "my_item_two". For this you'll have to use the positional "$" operator. Something like:
db.bar.update( {user_id : 123456 , "items.item_name" : "my_item_two" } ,
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postgresql COUNT(DISTINCT …) very slow
...the replies (by Jeff Janes) says that COUNT(DISTINCT()) sorts the table to do its work instead of using hash.
– Ankur
Dec 9 '14 at 10:58
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How do I get a distinct, ordered list of names from a DataTable using LINQ?
...Q statements.
First, select your data into a new list, let's call it x1, do a projection if desired
Next, create a distinct list, from x1 into x2, using whatever distinction you require
Finally, create an ordered list, from x2 into x3, sorting by whatever you desire
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Remove portion of a string after a certain character
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What about "only do this if "by" exists?
– Alisso
Apr 14 '13 at 5:00
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How can I return two values from a function in Python?
...llow framework returns a UnmarshalResult which is a namedtuple. So you can do:
data, errors = MySchema.loads(request.json())
if errors:
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or
result = MySchema.loads(request.json())
if result.errors:
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else:
# use `result.data`
In other cases you may return a dict from your func...
Where/How to getIntent().getExtras() in an Android Fragment? [duplicate]
With Activities, I used to do this:
2 Answers
2
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How can I find where Python is installed on Windows?
I want to find out my Python installation path on Windows. For example:
19 Answers
19
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How to find all links / pages on a website
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how do I do that myself? and what if there is no robots.txt in a web site?
– Alan Coromano
Jul 30 '13 at 17:15
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MySQL stored procedure vs function, which would I use when?
...olumn) FROM mytable is not valid if get_foo() is a procedure, but you can do that if get_foo() is a function. The price is that functions have more limitations than a procedure.
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Why is the C++ STL is so heavily based on templates? (and not on *interfaces*)
...t all it's cracked up to be. In many cases it is clumsy and verbose and it doesn't really promote reusable code or modularity.
That is why the C++ community is today far more interested in generic programming, and why everyone are finally starting to realize that functional programming is quite cle...