大约有 40,000 项符合查询结果（耗时：0.0698秒） [XML]
Best way to test SQL queries [closed]
...blem wherein we keep having complex SQL queries go out with errors. Essentially this results in sending mail to the incorrect customers and other 'problems' like that.
...
Overriding a Rails default_scope
...
Short answer: Do not use default_scope unless you really have to. You'll probably be better off with named scopes. With that said, you can use with_exclusive_scope to override the default scope if you need to.
Have a look at this question for more details.
...
What's the difference between IQueryable and IEnumerable
...;>), which can be thought of as "is the 'Age' property > 18".
This allows things like LINQ-to-SQL to exist because they can parse the expression tree and convert it into equivalent SQL. And because the provider doesn't need to execute until the IQueryable is enumerated (it implements IEnum...
Trying to embed newline in a variable in bash [duplicate]
...ar ) # Do not use double quotes "$var"
echo "$p"
Output is the same for all
a
b
c
Special thanks to contributors of this answer: kevinf, Gordon Davisson, l0b0, Dolda2000 and tripleee.
EDIT
See also BinaryZebra's answer providing many details.
Abhijeet Rastogi's answer and Dimitry's answer...
Compare two dates with JavaScript
...
@patrick, suggest calling setHours(0,0,0,0) this way. Eliminates the need for calling setMinutes() etc. Also, executes faster.
– Karl
Nov 16 '12 at 21:32
...
WPF: Setting the Width (and Height) as a Percentage Value
...ignment="Stretch" ...
That will make the Textbox element stretch horizontally and fill all the parent space horizontally (actually it depends on the parent panel you're using but should work for most cases).
Percentages can only be used with grid cell values so another option is to create a grid ...
How to get the host name of the current machine as defined in the Ansible hosts file?
...
The necessary variable is inventory_hostname.
- name: Install this only for local dev machine
pip: name=pyramid
when: inventory_hostname == "local"
It is somewhat hidden in the documentation at the bottom of this section.
...
Actual meaning of 'shell=True' in subprocess
I am calling different processes with the subprocess module. However, I have a question.
5 Answers
...
Returning null as an int permitted with ternary operator but not if statement
...ll trying to understand capture conversion and lub(T1,T2))?? Also, Is it really possible to apply boxing to a null value? Wouldn't this be like "guessing"??
– Marsellus Wallace
Nov 11 '11 at 21:03
...
pip install mysql-python fails with EnvironmentError: mysql_config not found
...
It seems mysql_config is missing on your system or the installer could not find it.
Be sure mysql_config is really installed.
For example on Debian/Ubuntu you must install the package:
sudo apt-get install libmysqlclient-dev
Maybe the mysql_config is not in your path, it will be ...