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How to make a new line or tab in XML (eclipse/android)?
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edited Mar 6 '17 at 10:27
aleksandrbel
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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the index, then retrieve the row from the heap...
How do I update zsh to the latest version?
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answered Jul 15 '13 at 8:30
Mike LiMike Li
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Append an object to a list in R in amortized constant time, O(1)?
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R>
That works on vectors too, so do I get the bonus points?
Edit (2015-Feb-01): This post is coming up on its fifth birthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(ol...
How can I get nth element from a list?
...re, the operator used is !!.
I.e. [1,2,3]!!1 gives you 2, since lists are 0-indexed.
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What is the difference between “def” and “val” to define a function
... time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
() => ...
What is default session timeout in ASP.NET?
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107
It is 20 Minutes according to MSDN
From MSDN:
Optional TimeSpan attribute.
Specifies the numbe...
How to create nonexistent subdirectories recursively using Bash?
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edited Jun 20 at 9:12
Community♦
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answered Nov 13 '09 at 20:42
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json.net has key method?
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svicksvick
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Convert any object to a byte[]
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201
Use the BinaryFormatter:
byte[] ObjectToByteArray(object obj)
{
if(obj == null)
re...