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What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
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ExecuteScalar is typically used when your query returns a single value. If it returns more, then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
ExecuteReader is used for any result set with m...
Why does DEBUG=False setting make my django Static Files Access fail?
Am building an app using Django as my workhorse. All has been well so far - specified db settings, configured static directories, urls, views etc. But trouble started sneaking in the moment I wanted to render my own beautiful and custom 404.html and 500.html pages.
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How to check which locks are held on a table
...other responses, sp_lock can also be used to dump full lock information on all running processes. The output can be overwhelming, but if you want to know exactly what is locked, it's a valuable one to run. I usually use it along with sp_who2 to quickly zero in on locking problems.
There are multi...
'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
What does '
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It's a shorthand for this:
<?php echo $a; ?>
They're called short tags; see example #2 in the documentation.
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How to test a merge without actually merging first
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@samirahmed: @Amber answered the question more literally, sure, although with --no-commit you're still changing the index and the working tree, which isn't exactly "without making any changes" :) My point is that when people ask this kind of question, it's generally because th...
How do you round UP a number in Python?
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Elaboration: math.ceil returns the smallest integer which is greater than or equal to the input value. This function treats the input as a float (Python does not have strongly-typed variables) and the function returns a float. If you want an int, you can constru...
Install Windows Service created in Visual Studio
...indows Service in Visual Studio 2010, I get the message stating to use InstallUtil and net start to run the service.
7 Answ...
Iterate over a Javascript associative array in sorted order
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You cannot iterate over them directly, but you can find all the keys and then just sort them.
var a = new Array();
a['b'] = 1;
a['z'] = 1;
a['a'] = 1;
function keys(obj)
{
var keys = [];
for(var key in obj)
{
if(obj.hasOwnProperty(key))
{
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How to make the hardware beep sound in Mac OS X 10.6
...ble hardware. Before most computers had sound cards, most machines had a small speaker or piezo buzzer connected to one of the channels of a timer chip. This could be used to generate simple tones or beeps. Even after many computers integrated sound cards, it remained common for quite some time for ...