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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...
Question mark (?) in XML attributes for Android
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edited Aug 31 '12 at 10:16
ubershmekel
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Segmentation fault on large array sizes
...d be fine, assuming your machine has enough memory.
int* array = new int[1000000];
But remember that this will require you to delete[] the array. A better solution would be to use std::vector<int> and resize it to 1000000 elements.
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Cross-referencing commits in github
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206
The answer, so us lazy people can find it without following the link to the Autolinked Referenc...
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
() => ...
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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MSTest copy file to test run folder
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edited Nov 22 '13 at 17:06
Richard Ev
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Java: possible to line break in a properties file?
...ot asked for.
– Enrice
Feb 26 at 15:05
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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...