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Truncating all tables in a Postgres database
I regularly need to delete all the data from my PostgreSQL database before a rebuild. How would I do this directly in SQL?
...
What is eager loading?
...hing when asked. Classic example is when you multiply two matrices. You do all the calculations. That's eager loading;
Lazy loading: you only do a calculation when required. In the previous example, you don't do any calculations until you access an element of the result matrix; and
Over-eager loadin...
How can I get the active screen dimensions?
...rn Screen.FromControl(this).Bounds;
}
}
I don't know of an equivalent call for WPF. Therefore, you need to do something like this extension method.
static class ExtensionsForWPF
{
public static System.Windows.Forms.Screen GetScreen(this Window window)
{
return System.Windows.Forms.Scree...
The import android.support cannot be resolved
... JARs Button on the Right pane.
Select the android-support-v4.jar file, usually the path for the Jar file is :
YOUR_DRIVE\android-sdks\extras\android\support\v4\android-support-v4.jar
After adding android-support-v4.jar Library, navigate to the Order and Export tab and put check mark on the android...
SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed
...L Certificate Authority (CA) bundle. You can do this with:
sudo port install curl-ca-bundle [if you are using MacPorts]
or just pull it down directly wget http://curl.haxx.se/ca/cacert.pem
Execute the ruby code that is trying to verify the SSL certification: SSL_CERT_FILE=/opt/local/etc/certs/ca...
How do I determine whether an array contains a particular value in Java?
...h FindBugs will tell you is very naughty. Do not modify statics and do not allow other code to do so also. At an absolute minimum, the field should be private:
private static final String[] VALUES = new String[] {"AB","BC","CD","AE"};
(Note, you can actually drop the new String[]; bit.)
Reference a...
Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
List directory tree structure in python?
I know that we can use os.walk() to list all sub-directories or all files in a directory. However, I would like to list the full directory tree content:
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Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
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How to force link from iframe to be opened in the parent window
...of the page in the iframe:
<base target="_parent">
This will load all links on the page in the parent window. If you want your links to load in a new window, use:
<base target="_blank">
This tag is fully supported in all browsers.
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