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MySQL: @variable vs. variable. What's the difference?
...ialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stored procedure in MySQL, you can pass the input parameters and declare the local variables:
DELIMITER //
CREATE PROCEDURE prc_test (var INT)
BEGIN
DECLARE var2 INT;
SET var2 =...
Aggregate function in an SQL update query?
...
UPDATE t1
SET t1.field1 = t2.field2Sum
FROM table1 t1
INNER JOIN (select field3, sum(field2) as field2Sum
from table2
group by field3) as t2
on t2.field3 = t1.field3
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improve...
How to play with Control.Monad.Writer in haskell?
...ype of logNumber is logNumber :: (Show a, Monad m) => a -> WriterT [[Char]] m a for me.
– kmikael
May 27 '15 at 20:15
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How to check file MIME type with javascript before upload?
...d see three remote images of different types displayed. At the top you can select a local image or data file, and the file signature and/or MIME type will be displayed.
Notice that even if an image is renamed, its true MIME type can be determined. See below.
Screenshot
// Return the first...
What's the false operator in C# good for?
...he operator false declared in T, and T.&(x, y) is an invocation of the selected operator &. In other words, x is first evaluated and operator false is invoked on the result to determine if x is definitely false. Then, if x is definitely false, the result of the operation is the value previou...
Changing case in Vim
Is there a command in Vim that changes the case of the selected text?
2 Answers
2
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How to find children of nodes using BeautifulSoup
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This answers the question how to select <a>link1</a> in the HTML given in the question, but this will FAIL when the first <li class="test"> will contain no <a> elements and there are other li elements with test class that contains<...
How do I enter RGB values into Interface Builder?
... enter RGB or Hex color values for backgrounds in Interface Builder? I can select predefined colors but I would like to manually enter in RGB values. Where can I do this?
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How many spaces will Java String.trim() remove?
...tation means by "whitespace". It would seem logical that it would be where Chararacter.isWhitespace is true, but that is not what it means by "whitespace" ..
– user2864740
Nov 30 '13 at 9:17
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Paste multiple times
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Clever. 'p' to paste, 'gv' to re-select what was originally selected. 'y' to copy it again.
– Amjith
Aug 23 '11 at 21:17
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