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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
Select unique or distinct values from a list in UNIX shell script
...n the following input:
class
jar
jar
jar
bin
bin
java
uniq will output all lines exactly once:
class
jar
bin
java
uniq -d will output all lines that appear more than once, and it will print them once:
jar
bin
uniq -u will output all lines that appear exactly once, and it will print them ...
What can , and be used for?
...iewParam name="id" value="#{bean.id}" />
</f:metadata>
does basically the following:
Get the request parameter value by name id.
Convert and validate it if necessary (you can use required, validator and converter attributes and nest a <f:converter> and <f:validator> in it like...
Drawing a connecting line between two elements [closed]
...ilding applications and integrations for popular libraries, and is commercially licensed.
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How to get the IP address of the docker host from inside a docker container
...r, that's what bridge IP can give you (of course in the stndard "home" installation). Why anybody would need "real" host IP if it can be even outside of docker bridge and can be unaccessible? This is the solution for all people who just installed docker and want to play with it in a short time.
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How do I install an R package from source?
...nt me along this great tutorial on webscraping NYtimes with R . I would really love to try it. However, the first step is to installed a package called RJSONIO from source.
...
Read logcat programmatically within application
...ded before the clear completes. It doesn't make a difference even if you call process.waitfor().
– Tom Rutchik
Jun 3 at 0:25
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I can't install python-ldap
...n order to compile the Python module. If you're on Ubuntu, the package is called libldap2-dev.
Debian/Ubuntu:
sudo apt-get install libsasl2-dev python-dev libldap2-dev libssl-dev
RedHat/CentOS:
sudo yum install python-devel openldap-devel
...
Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
How does one create an InputStream from a String? [duplicate]
...may not be the one you want here). For me, this is UTF-8 (which can encode all Java Strings). The right answer would be "indicate the encoding you really want", not "use UTF-16". And you can use it with .getBytes(charsetName), don't have to explicitly create a Charset object and encode the String to...