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Best way to test if a row exists in a MySQL table
...ng':
SELECT * FROM test WHERE texte LIKE '%something%' LIMIT 1 with
mysql_num_rows() : 0.039061069488525s. (FASTER)
SELECT count(*) as count FROM test WHERE text LIKE '%something% :
16.028197050095s.
SELECT EXISTS(SELECT 1 FROM test WHERE text LIKE '%something%') :
0.87045907974243s.
SELECT EXIS...
Django FileField with upload_to determined at runtime
...ng to set up my uploads so that if user joe uploads a file it goes to MEDIA_ROOT/joe as opposed to having everyone's files go to MEDIA_ROOT. The problem is I don't know how to define this in the model. Here is how it currently looks:
...
Rails 2.3-style plugins and deprecation warnings running task in Heroku
...x applications ..
To avoid this
injection in Rails 3, include the rails_12factor gem in your
application. (Heroku Ruby Support 2013-10-26)
The rails_12factor gem is also required in rails 4.
If this gem is not present in your application, you will receive a
warning while deploying, and...
Scala equivalent of Java java.lang.Class Object
...: java.lang.Class[C] = class C
scala> c.getClass
res1: java.lang.Class[_] = class C
That is why the following will not work:
val xClass: Class[X] = new X().getClass //it returns Class[_], nor Class[X]
val integerClass: Class[Integer] = new Integer(5).getClass //similar error
There is a ticket...
How do I use HTML as the view engine in Express?
... routing. Instead, just use the static middleware:
app.use(express.static(__dirname + '/public'));
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Pythonic way to print list items
...myList, sep='\n')
You can get the same behavior on Python 2.x using from __future__ import print_function, as noted by mgilson in comments.
With the print statement on Python 2.x you will need iteration of some kind, regarding your question about print(p) for p in myList not working, you can just...
Datepicker: How to popup datepicker when click on edittext
...e:
<EditText
android:id="@+id/Birthday"
custom:font="@string/font_avenir_book"
android:clickable="true"
android:editable="false"
android:hint="@string/birthday"/>
Now in Java File:
final Calendar myCalendar = Calendar.getInstance();
EditText edittext= (EditText) findViewByI...
“is” operator behaves unexpectedly with integers
...tively rare. Here's an example (will work in Python 2 and 3) e.g.
SENTINEL_SINGLETON = object() # this will only be created one time.
def foo(keyword_argument=None):
if keyword_argument is None:
print('no argument given to foo')
bar()
bar(keyword_argument)
bar('baz')
def b...
Apply multiple functions to multiple groupby columns
...ame, you can use a normal function and supply a custom name to the special __name__ attribute like this:
def max_min(x):
return x.max() - x.min()
max_min.__name__ = 'Max minus Min'
df.groupby('group').agg({'a':['sum', 'max'],
'b':'mean',
'c'...
Best practices for in-app database migration for Sqlite
...t/set this variable with the following sqlite statements:
> PRAGMA user_version;
> PRAGMA user_version = 1;
When the app starts, I check the current user-version, apply any changes that are needed to bring the schema up to date, and then update the user-version. I wrap the updates in a t...
