大约有 3,800 项符合查询结果(耗时:0.0291秒) [XML]

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How to Select Every Row Where Column Value is NOT Distinct

...mailAddress] must appear in the GROUP BY clause or be used in an aggregate function error. Is the only fix - editing the sql_mode? – Volodymyr Bobyr Jul 16 at 16:21 ...
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Determine the number of NA values in a column

... In counting amount of arbitrary value, other than NA is writing a boolean function is.value and then using sum(is.value(df$col)) the way to go or is there a more concise direct syntax for this? – user3274289 Jun 4 '14 at 2:11 ...
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Why does this (null || !TryParse) conditional result in “use of unassigned local variable”?

...l repro: class Program { static bool M(out int x) { x = 123; return true; } static int N(dynamic d) { int y; if(d || M(out y)) y = 10; return y; } } I see no reason why that should be illegal; if you replace dynamic ...
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Getting the first index of an object

... Just for fun this works in JS 1.8.5 var obj = {a: 1, b: 2, c: 3}; Object.keys(obj)[0]; // "a" This matches the same order that you would see doing for (o in obj) { ... } ...
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How do I extract text that lies between parentheses (round brackets)?

...e (sales)", @"\(([^)]*)\)").Groups[1].Value As a response to the (very funny) comment, here's the same Regex with some explanation: \( # Escaped parenthesis, means "starts with a '(' character" ( # Parentheses in a regex mean "put (capture) the stuff # ...
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How to check whether a file is empty or not?

...size() and stat() will throw an exception if the file does not exist. This function will return True/False without throwing (simpler but less robust): import os def is_non_zero_file(fpath): return os.path.isfile(fpath) and os.path.getsize(fpath) > 0 ...
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Working Soap client example

...@gmail.com</example:email> <example:LicenseKey>123</example:LicenseKey> </example:VerifyEmail> </SOAP-ENV:Body> </SOAP-ENV:Envelope> */ // SOAP Body SOAPBody soapBody = envelope.getBody(); SOAPElement soapB...
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What's the best/easiest GUI Library for Ruby? [closed]

... Shoes is not made for production environment but for fun, it is the "turtle graphic" of Ruby. It is intended for newbies to get acquainted with 1.) domain specific language, 2.) graphics – karatedog Feb 2 '12 at 11:58 ...
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Delete multiple records using REST

...'ve allowed for a wholesale replacement of a collection, e.g. PUT ~/people/123/shoes where the body is the entire collection representation. This works for small child collections of items where the client wants to review a the items and prune-out some and add some others in and then update the ser...
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Android and setting width and height programmatically in dp units

... @RomainGuy, can you please add a utility function to the API to convert from dp to px? Thanks. – AlikElzin-kilaka May 6 '13 at 14:22 ...