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Cannot delete or update a parent row: a foreign key constraint fails
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If you were going to do this, why not just remove all of the constraints?
– Sablefoste
Jun 7 '16 at 12:23
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How to Disable landscape mode in Android?
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Add android:screenOrientation="portrait" to the activity in the AndroidManifest.xml. For example:
<activity android:name=".SomeActivity"
android:label="@string/app_name"
android:screenOrientation="portrait" />
EDIT: Since this has become a super-popular answer, I feel very guilty a...
In C++, if throw is an expression, what is its type?
...ument to most operators. Obviously, you can hide them in parenthesis, but if they aren't ignored (first argument of builtin operator , for instance), it is a type error.
– AProgrammer
Jul 31 '09 at 15:21
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What should I use Android AccountManager for?
...Provider ties into ContentResolver's observer: this means it is easy to notify views when content is changed
Bottom line: the framework AccountManager / SyncAdapter / ContentProvider helps if you want to synchronize data from a web resource. Fake/Dumb implementations are required on API 7. Also
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Extracting substrings in Go
...confused by the working of slices and the string storage format, which is different from what you have in C.
any slice in Go stores the length (in bytes), so you don't have to care about the cost of the len operation : there is no need to count
Go strings aren't null terminated, so you don't have ...
How to add a new method to a php object on the fly?
...his:
class Foo
{
public function __call($method, $args)
{
if (isset($this->$method)) {
$func = $this->$method;
return call_user_func_array($func, $args);
}
}
}
$foo = new Foo();
$foo->bar = function () { echo "Hello, this function is add...
How to check whether a variable is a class or not?
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If you also want inspect.isclass to return True if the object to inspect is a class instance, use inspect.isclass(type(Myclass()))
– michaelmeyer
Apr 18 '13 at 16:21
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Change SVN repository URL
...locate is used when the SVN server's location changes. switch is only used if you want to change your local working copy to another branch or another path. If using TortoiseSVN, you may follow instructions from the TortoiseSVN Manual. If using the SVN command line interface, refer to this section o...
size_t vs. uintptr_t
...the offset within it). I know these things sound weird in these days of uniformly addressable unsegmented architectures, but the standard MUST cater for a wider variety than "what's normal in 2009", you know!-)
share
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How to concatenate columns in a Postgres SELECT?
... mean "returns NULL". The result of anything concatenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separ...