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Django - How to rename a model field using South?
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Django 1.7 introduced Migrations so now you don't even need to install extra package to manage your migrations.
To rename your model you need to create empty migration first:
$ manage.py makemigrations <app_name> --empty
Then you need to edit your migration's code like this:
from djan...
Creating JS object with Object.create(null)?
... in the map that you never inserted. For example, if you did a lookup on toString, you would find a function, even though you never put that value there. You can work around that like this:
if (Object.prototype.hasOwnProperty.call(p, 'toString')) {
// we actually inserted a 'toString' key into p...
How to check visibility of software keyboard in Android?
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Some keyboards, some of the time, have an extra row of custom keys on top (for instance, predicted words). These are apparently not part of the keyboard itself, since using the getLastKeyboardHeightInPx() does not include the height of that row. Do you know of a way ...
How to exclude certain directories/files from git grep search
... separate list $moved. I had issues with whitespace in
# the search-string, so this is loosely based on:
# http://www.linuxjournal.com/content/bash-preserving-whitespace-using-set-and-eval
x=1 ...
Clicking the text to select corresponding radio button
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Another option to avoid the extra space between the radio button and label, is to simply not put it there <input id="349" type="radio" value="1" name="question1"><label for="349"> Abe</label> (no spaces or newlines between the tags)
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Difference between margin and padding?
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Remember these 3 points:
The Margin is the extra space around the control.
The Padding is extra space inside the control.
The Padding of an outer control is the Margin of an inner control.
Demo Image:(where red box is desire control)
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How to implement a rule engine?
... all operators before compiling the rules:
var nameMap = new Dictionary<string, string> {
{ "greater_than", "GreaterThan" },
{ "hasAtLeastOne", "Contains" }
};
The code uses the type User for simplicity. You can replace User with a generic type T to have a generic Rule compiler for an...
Eager load polymorphic
...w you join a table named by the value stored in a column. By defining the extra relationship belongs_to :shop, you are giving ActiveRecord the information it needs to complete the join.
share
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imp...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
...atabase file.
catch is the constructor
SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)
So when the database helper constructor is called with a name (2nd param), platform checks if the database exists or not and if the database exists, it gets th...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...esn't use quotes inside the schema definition
MySQL uses single quotes for strings inside the INSERT INTO clauses
SQLite and MySQL have different ways of escaping strings inside INSERT INTO clauses
SQLite uses 't' and 'f' for booleans, MySQL uses 1 and 0 (a simple regex for this can fail when you ha...