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Best way to test if a row exists in a MySQL table
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Test with ...EXISTS( SELECT 1/0 FROM someothertable). For SQL Server & Oracle - it makes no difference to use *, 1 or NULL because EXISTS only tests for a boolean based on 1+ of the WHERE criteria matching.
– OMG Ponies
Nov 4 '09 at 23:...
In PHP, how do you change the key of an array element?
I have an associative array in the form key => value where key is a numerical value, however it is not a sequential numerical value. The key is actually an ID number and the value is a count. This is fine for most instances, however I want a function that gets the human-readable name of the arr...
Replace values in list using Python [duplicate]
...d a new list with a list comprehension:
new_items = [x if x % 2 else None for x in items]
You can modify the original list in-place if you want, but it doesn't actually save time:
items = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
for index, item in enumerate(items):
if not (item % 2):
items...
Why do we need tuples in Python (or any immutable data type)?
I've read several python tutorials (Dive Into Python, for one), and the language reference on Python.org - I don't see why the language needs tuples.
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Fragment transaction animation: slide in and slide out
I've check some tutorials for animate transaction between fragments. I've used this method for animation and it works:
5 An...
How can I change an element's text without changing its child elements?
...im: ah, I thought there must be an easier way. Never did much JavaScript before jQuery came along. Cheers, I’ll edit the answer accordingly.
– Paul D. Waite
Nov 5 '10 at 16:22
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How to Reverse Fragment Animations on BackStack?
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According to the android documentation for custom animation:
Change:
ft.setCustomAnimations(R.anim.slide_in, R.anim.hyperspace_out);
To:
ft.setCustomAnimations(R.anim.slide_in, R.anim.hyperspace_out, R.anim.hyperspace_in, R.anim.slide_out );
and now the bac...
Alter MySQL table to add comments on columns
I have been checking the MySQL Documentation for ALTER TABLE and it does not seem to include a way to add or modify a comment to a column. How can I do this?
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Android: how to make keyboard enter button say “Search” and handle its click?
...) {
if (actionId == EditorInfo.IME_ACTION_SEARCH) {
performSearch();
return true;
}
return false;
}
});
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The tilde operator in Python
...eration, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement representation of the integer are reversed (as in b <- b XOR 1 for each individual bit), and the result interpreted again as a twos-complement integer. So for integers, ~x is ...