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Why array implements IList?
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Because an array allows fast access by index, and IList/IList<T> is are the only collection interfaces that support this. So perhaps your real question is "Why is there no interface for constant collections with indexers?" And to that I have no answer.
Ther...
z-index not working with position absolute
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The second div is position: static (the default) so the z-index does not apply to it.
You need to position (set the position property to anything other than static, you probably want relative in this case) anything you want to give a z-index to.
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Why in Java 8 split sometimes removes empty strings at start of result array?
...2.
Java 7
public String[] split(CharSequence input, int limit) {
int index = 0;
boolean matchLimited = limit > 0;
ArrayList<String> matchList = new ArrayList<>();
Matcher m = matcher(input);
// Add segments before each match found
while(m.find()) {
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How to get the nth element of a python list or a default if not available
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l[index] if index < len(l) else default
To support negative indices we can use:
l[index] if -len(l) <= index < len(l) else default
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What's the use/meaning of the @ character in variable names in C#?
...e. I believe this may be because of the familiarity of this requirement in PHP software for variables. And a lot of Open Source web systems are now coded in C# (where in the past it would have been PHP)
– Wasted_Coder
Mar 5 '16 at 19:36
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What is cardinality in MySQL?
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It is an estimate of the number of unique values in the index.
For a table with a single primary key column, the cardinality should normally be equal to the number of rows in the table.
More information.
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A migration to add unique constraint to a combination of columns
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add_index :people, [:firstname, :lastname, :dob], :unique => true
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Convert a Unix timestamp to time in JavaScript
...mat() library, which implements JavaScript date formatting in the style of PHP's date() function.
new Date(unix_timestamp * 1000).format('h:i:s')
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How can I declare and define multiple variables in one line using C++?
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int column = 0, row = 0, index = 0;
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How to implement a unique index on two columns in rails
I have a table and I'm trying to add a unique index on two columns. Those columns are also indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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