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Check if a Class Object is subclass of another Class Object in Java
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if (o instanceof Number) {
double d = ((Number)o).doubleValue(); //this cast is safe
}
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How do I execute a stored procedure once for each row returned by query?
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declare @field1 int
declare @field2 int
declare cur CURSOR LOCAL for
select field1, field2 from sometable where someotherfield is null
open cur
fetch next from cur into @field1, @field2
while @@FETCH_STATUS = 0 BEGIN
--execute your sproc on each row
exec uspYourSproc @field1, @fiel...
Postgres: INSERT if does not exist already
...onditional INSERT in PostgreSQL:
INSERT INTO example_table
(id, name)
SELECT 1, 'John'
WHERE
NOT EXISTS (
SELECT id FROM example_table WHERE id = 1
);
CAVEAT This approach is not 100% reliable for concurrent write operations, though. There is a very tiny race condition between...
Modifying location.hash without page scrolling
... load
if(document.location.hash){
$("#buttons li a").removeClass('selected');
s=$(document.location.hash.replace("btn_","")).addClass('selected').attr("href").replace("javascript:","");
eval(s);
}
//Click a button to change the hash
$("#buttons li a").click(function()...
SQL Server indexes - ascending or descending, what difference does it make?
...TE INDEX ix_index ON mytable (col1, col2 DESC);
can be used for either:
SELECT *
FROM mytable
ORDER BY
col1, col2 DESC
or:
SELECT *
FROM mytable
ORDER BY
col1 DESC, col2
, but not for:
SELECT *
FROM mytable
ORDER BY
col1, col2
An index on a single colum...
Meaning of acronym SSO in the context of std::string
...h_resolution_clock::now();
const auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(t2 - t1).count();
std::cerr << list[0].length() << ',' << duration << '\n';
}
void addRandomString(std::vector<std::string>& list, const int length)...
Hidden Features of Visual Studio (2005-2010)?
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Make a selection with ALT pressed - selects a square of text instead of whole lines.
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answered Sep 19 ...
How can I add the new “Floating Action Button” between two widgets/layouts
...anchor causing me a rendering problem (linearlayout layoutparams cannot be cast to coordinatorlayout. :(
– DAVIDBALAS1
Aug 23 '16 at 18:43
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Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY,...
Is it possible to center text in select box?
...you could style the dropdown:
https://www.filamentgroup.com/lab/jquery-ui-selectmenu-an-aria-accessible-plugin-for-styling-a-html-select.html
This plugin hides the select element, and creates span elements etc on the fly to display a custom drop down list style. I'm quite confident you'd be able t...