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Django 1.7 throws django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet

...t os from django.core.handlers.wsgi import WSGIHandler os.environ['DJANGO_SETTINGS_MODULE'] = 'myapp.settings' application = WSGIHandler() When I updated to the 1.7 style WSGI handler: import os from django.core.wsgi import get_wsgi_application os.environ['DJANGO_SETTINGS_MODULE'] = 'myapp.se...
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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...
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App Inventor 2 数学代码块 · App Inventor 2 中文网

...言的算术右移 >> 语义一致。 参考代码如下: when 按钮_左移.Click() { 标签_结果.Text = 5 * 2 } when 按钮_右移.Click() { 标签_结果.Text = floor(5 / 2) } 通用函数版本:把位数做成参数,任何值、移多少位都能用(左移 = ×2ⁿ,右移 = ...
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Completion handler for UINavigationController “pushViewController:animated”?

...rface UINavigationController (CompletionHandler) - (void)completionhandler_pushViewController:(UIViewController *)viewController animated:(BOOL)animated completion:(void (^)(void))completion; @end Implementation: #import "UIN...
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How to implement a rule engine?

...; // use a method call, e.g. 'Contains' -> 'u.Tags.Contains(some_tag)' return Expression.Call(left, method, right); } } Note that I used 'GreaterThan' instead of 'greater_than' etc. - this is because 'GreaterThan' is the .NET name for the operator, therefore we don't need any...
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How to query SOLR for empty fields?

...ou need to change QueryParameter.cs (Create a new parameter) private bool _negativeQuery = false; public QueryParameter(string field, string value, ParameterJoin parameterJoin = ParameterJoin.AND, bool negativeQuery = false) { this._field = field; this._value = value.Trim(); this._para...
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How do you use the ellipsis slicing syntax in Python?

...'d use it like this: >>> class TestEllipsis(object): ... def __getitem__(self, item): ... if item is Ellipsis: ... return "Returning all items" ... else: ... return "return %r items" % item ... >>> x = TestEllipsis() >>> print ...
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Subprocess changing directory

... @The_Diver That's why cd must be implemented as internal shell command. There's no other way to do it. Internal shell commands are executed within the same process as the shell. What I meant by subshell is the shell executed for ...
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Weak and strong property setter attributes in Objective-C

...n release autorelease etc... Instead you use strong weak for properties or __strong __weak for variables (defaults to __strong). Strong is the equivalent to retain, however ARC will manage the release for you. The only time you would want to use weak, is if you wanted to avoid retain cycles (e.g...
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How to select multiple files with ?

...ltiple="multiple" and if you are using php then you will get the data in $_FILES and use var_dump($_FILES) and see output and do processing Now you can iterate over and do the rest share | improve...