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Select DISTINCT individual columns in django?
...g note in the docs about using distinct(). The above example will work but all combinations of distinct() and values() may not.
PS: it is a good idea to use lower case names for fields in a model. In your case this would mean rewriting your model as shown below:
class ProductOrder(models.Model):
...
Maven dependency for Servlet 3.0 API?
...JSTL 1.2, JSF 2.0, JTA 1.1, JSR-45, JSR-250.
But to my knowledge, nothing allows to say that these APIs won't be distributed separately (in java.net repository or somewhere else). For example (ok, it may a particular case), the JSF 2.0 API is available separately (in the java.net repository):
<...
Can not connect to local PostgreSQL
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This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...
What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?
Can anybody give a clear explanation of how variable assignment really works in Makefiles.
6 Answers
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Squash my last X commits together using Git
...e difference between this rebase -i approach and reset --soft is, rebase -iallows me to retain the commit author, while reset --soft allows me to recommit. Sometimes i need to squash commits of pull requests yet maintaining the author information. Sometimes i need to reset soft on my own commits. ...
Input text dialog Android
...et it as the view of the AlertDialog. You can customize the type of input allowed using setInputType, if you need.
If you're able to use a member variable, you can simply set the variable to the value of the EditText, and it will persist after the dialog has dismissed. If you can't use a member v...
How does “make” app know default target to build if no target is specified?
...e default goal; to do that, it may have to process other targets - specifically, ones the first target depends on.
The GNU Make Manual covers all this stuff, and is a surprisingly easy and informative read.
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What is the difference between ports 465 and 587?
...g SMTP protocol.
Port 465 is for smtps
SSL encryption is started automatically before any SMTP level communication.
Port 587 is for msa
It is almost like standard SMTP port.
MSA should accept email after authentication (e.g. after SMTP AUTH). It helps to stop outgoing spam when netmasters of DUL r...
How do you use colspan and rowspan in HTML tables?
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If you're confused how table layouts work, they basically start at x=0, y=0 and work their way across. Let's explain with graphics, because they're so much fun!
When you start a table, you make a grid. Your first row and cell will be in the top left corner. Think of it like an...