大约有 40,000 项符合查询结果(耗时:0.1165秒) [XML]

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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?

...an work around it from within psql by executing the DDL statement conditionally: SELECT 'CREATE DATABASE mydb' WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec The manual: \gexec Sends the current query buffer to the server, then treats each column of each row of the query's...
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Email validation using jQuery

...ming more common this regex may need modifying .systems and .poker etc are all valid TLDs now but would fail the regex check – Liath Sep 5 '14 at 7:35 3 ...
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Does height and width not apply to span?

...ides no context to indicate that a div is inherently inappropriate semantically. – Isaac Mar 22 '10 at 9:45 1 ...
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How to get memory available or used in C#

... It should probably be noted that a call to GetCurrentProcess will itself allocate quite a lot of resources. Call Dispose on the returned process when done, or wrap the whole code in a "using" scope. – Mathias Lykkegaard Lorenzen ...
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How to get the current date/time in Java [duplicate]

...is page ;-) – Dave Mar 12 '19 at 15:32 add a comment  |  ...
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How to deselect a selected UITableView cell?

...dexPath – El Tomato Mar 2 '13 at 12:32 this is not supported on iOS 11 Swift 4 – Boris Nikolic ...
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How do I concatenate two lists in Python?

... @Daniel it will create a new list with a shallow copy of the items in the first list, followed by a shallow copy of the items in the second list. Use copy.deepcopy to get deep copies of lists. – Daniel G Apr 19 '12 at 14:51 ...
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How do you clear a stringstream variable?

... For all the standard library types the member function empty() is a query, not a command, i.e. it means "are you empty?" not "please throw away your contents". The clear() member function is inherited from ios and is used to cle...
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How can I efficiently select a Standard Library container in C++11?

...ited May 16 '16 at 7:29 user2508324 answered May 22 '12 at 11:26 Matthieu M.Matthieu M. ...
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Outputting data from unit test in python

... %r", self.that ) # etc. self.assertEquals( 3.14, pi ) if __name__ == "__main__": logging.basicConfig( stream=sys.stderr ) logging.getLogger( "SomeTest.testSomething" ).setLevel( logging.DEBUG ) unittest.main() That allows us to turn on debugging for specific tests whi...