大约有 44,000 项符合查询结果(耗时:0.0448秒) [XML]

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right click context menu for datagridview

...d like to rightclick on a row and have a menu pop up. Then i would like to select things such as copy, validate, etc 7 Answ...
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Computed / calculated / virtual / derived columns in PostgreSQL

...y as column? The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly. Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like: CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
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What is the advantage of using heredoc in PHP? [closed]

...e day I used to use them to construct SQL queries: $sql = <<<SQL select * from $tablename where id in [$order_ids_list] and product_name = "widgets" SQL; To me this has a lower probability of introducing a syntax error than using quotes: $sql = " select * from $tablename where ...
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Why is setTimeout(fn, 0) sometimes useful?

... recently run into a rather nasty bug, wherein the code was loading a <select> dynamically via JavaScript. This dynamically loaded <select> had a pre-selected value. In IE6, we already had code to fix the selected <option> , because sometimes the <select> 's selected...
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Is short-circuiting logical operators mandated? And evaluation order?

...h C and C++. If it wasn't, code like this would not be a common idiom char* pChar = 0; // some actions which may or may not set pChar to something if ((pChar != 0) && (*pChar != '\0')) { // do something useful } Section 6.5.13 Logical AND operator of the C99 specificat...
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How can I get the behavior of GNU's readlink -f on a Mac?

...es, sys libc = ctypes.CDLL('libc.dylib') libc.realpath.restype = ctypes.c_char_p libc.__error.restype = ctypes.POINTER(ctypes.c_int) libc.strerror.restype = ctypes.c_char_p def realpath(path): buffer = ctypes.create_string_buffer(1024) # PATH_MAX if libc.realpath(path, buffer): ret...
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Is it possible to GROUP BY multiple columns using MySQL?

Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example: 7 Answers ...
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How to resume Fragment from BackStack if exists

...teName); ft.commit(); } } The conditional was changed a bit since selecting the same fragment while it was visible also caused duplicate entries. Implementation: I highly suggest not taking the the updated replaceFragment() method apart like you did in your code. All the logic is containe...
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SQL Server - Create a copy of a database table and place it in the same database?

... Use SELECT ... INTO: SELECT * INTO ABC_1 FROM ABC; This will create a new table ABC_1 that has the same column structure as ABC and contains the same data. Constraints (e.g. keys, default values), however, are -not- copied. ...
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How to get the index of an element in an IEnumerable?

... extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist – Michael Mar 19 '14 at 16:05 ...