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How to get number of rows using SqlDataReader in C#
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There are only two options:
Find out by reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete ...
git command to show all (lightweight) tags creation dates
Is there a one liner that shows me the dates where all git lightweight tags where created ?
2 Answers
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Retain precision with double in Java
...red as a binary representation of a fraction and a exponent.
More specifically, a double-precision floating point value such as the double type is a 64-bit value, where:
1 bit denotes the sign (positive or negative).
11 bits for the exponent.
52 bits for the significant digits (the fractional par...
Android adding simple animations while setvisibility(view.Gone)
...yout like changing view visibility or view positions android will automatically create fade/transition animations. To use that set
android:animateLayoutChanges="true"
on the root node in your layout.
Your second option would be to manually add animations. For this I suggest you use the new anim...
Regex for string not ending with given suffix
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I don't know RegexPAL, but regexes are different in all languages and lookbehind assertions are an advanced feature that is not supported by all.
– stema
May 6 '13 at 12:47
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How to detect IE11?
...changes it's intentional to avoid mis-detection.
What you can do if you really want to know it's IE is to detect the Trident/ string in the user agent if navigator.appName returns Netscape, something like (the untested);
function getInternetExplorerVersion()
{
var rv = -1;
if (navigator...
Reference alias (calculated in SELECT) in WHERE clause
...probably consider a computed column (and perhaps persisted) instead, especially if a lot of queries refer to this same expression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform the calculation once, even though you've referenced it twice. ...
I forgot the password I entered during postgres installation
I either forgot or mistyped (during the installation) the password to the default user of Postgres. I can't seem to be able to run it and I get the following error:
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What does an Asterisk (*) do in a CSS selector?
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It is a wildcard, this means it will select all elements within that portion of the DOM.
For example, if I want apply margin to every element on my entire page you can use:
* {
margin: 10px;
}
You can also use this within sub-selections, for example the followi...
Official way to ask jQuery wait for all images to load before executing something
... DOM is loaded and $(window).on("load", handler) to execute something when all other things are loaded as well, such as the images.
The difference can be seen in the following complete HTML file, provided you have a jollyroger JPEG files (or other suitable ones):
<html>
<head>
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