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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...
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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: ...
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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...
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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...
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How do I use HTML as the view engine in Express?

... routing. Instead, just use the static middleware: app.use(express.static(__dirname + '/public')); share | improve this answer | follow | ...
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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...
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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...
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“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...
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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'...
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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...