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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 ...
How do I find which program is using port 80 in Windows? [duplicate]
... Then you either need to watch through list carefully or install some additional software. technet.microsoft.com/en-us/sysinternals/bb897437.aspx for example.
– n0rd
Dec 25 '09 at 8:14
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What does “Changes not staged for commit” mean
...epository, you have to git add it again if you want it to be staged.
This allows you to commit only a subset of the changes you made since the last commit. For example, let's say you have file a, file b and file c. You modify file a and file b but the changes are very different in nature and you do...
How to remove constraints from my MySQL table?
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Postgres, MSSQL, and Oracle all have alter table .. drop constraint. MySQL is the odd one out, it seems.
– Jared Beck
Mar 23 '15 at 23:48
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Installation Issue with matplotlib Python [duplicate]
I have issue after installing the matplotlib package unable to import matplotlib.pyplot as plt . Any suggestion will be greatly appreciate.
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What is the Python equivalent of static variables inside a function?
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there is only one instance of foo - this one function. all invocations access the same variable.
– Claudiu
Nov 10 '08 at 23:49
124
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Add a column with a default value to an existing table in SQL Server
...ed for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.
How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
Execute another jar in a Java program
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.jar isn't executable. Instantiate classes or make call to any static method.
EDIT:
Add Main-Class entry while creating a JAR.
>p.mf (content of p.mf)
Main-Class: pk.Test
>Test.java
package pk;
public class Test{
public static void main(String []args){
Sys...
Foreign Key naming scheme
...o qualify this. It's an unusual situation to be in, and not one you'd typically design in from scratch, so I didn't include this in the response.
– Greg Beech
Oct 14 '08 at 0:41
4
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Remove a file from a Git repository without deleting it from the local filesystem
...ged content has to match either the tip of the branch or the file on disk, allowing the file to be removed from just the index.
So, for a single file:
git rm --cached mylogfile.log
and for a single directory:
git rm --cached -r mydirectory
...