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MySQL foreign key constraints, cascade delete
I want to use foreign keys to keep the integrity and avoid orphans (I already use innoDB).
3 Answers
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Why do we use arrays instead of other data structures?
...gured the added "features" in programming languages had improved upon this and by that replaced them. I see now that they aren't replaced but rather given new life, so to speak.
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How to split last commit into two in Git
I have two working branches, master and forum and I've just made some modifications in forum branch, that I'd like to cherry-pick into master . But unfortunately, the commit I want to cherry-pick also contains some modifications that I don't want.
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Unable to find the wrapper “https” - did you forget to enable it when you configured PHP?
...stion. I've done a thorough investigation for solutions in regards to this and I know there are topics to this and I've followed them too and nothing has worked. That being said I'll list out exactly everything I've done so far. I am running PHP 5.2.14 with Zend Debugging on the latest Eclipse versi...
Custom bullet symbol for elements in that is a regular character, and not an image
...ides a straightforward solution. Simply add list-style: none; to your rule and force the LIs to display with hanging indents. The rule will look something like this:
ul {
list-style: none;
margin-left: 0;
padding-left: 1em;
text-indent: -1em;
}
Either the padding or the margin needs to ...
Is it possible to use argsort in descending order?
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If you negate an array, the lowest elements become the highest elements and vice-versa. Therefore, the indices of the n highest elements are:
(-avgDists).argsort()[:n]
Another way to reason about this, as mentioned in the comments, is to observe that the big elements are coming last in the ar...
How to get the last char of a string in PHP?
...o get the last character of a string.
Say I have "testers" as input string and I want the result to be "s". how can I do that in PHP?
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Can you break from a Groovy “each” closure?
...ndition.
Alternatively, you could use a "find" closure instead of an each and return true when you would have done a break.
This example will abort before processing the whole list:
def a = [1, 2, 3, 4, 5, 6, 7]
a.find {
if (it > 5) return true // break
println it // do the stuff th...
Python list subtraction operation
...set(x) - set(y))
>>> z
[0, 8, 2, 4, 6]
Or you might just have x and y be sets so you don't have to do any conversions.
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Test if lists share any items in python
... generally the fastest.
There are four common ways to test if two lists a and b share any items. The first option is to convert both to sets and check their intersection, as such:
bool(set(a) & set(b))
Because sets are stored using a hash table in Python, searching them is O(1) (see here for...