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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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change html text from link with jquery
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edited Jun 20 at 9:12
Community♦
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answered May 23 '09 at 17:06
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...%: %> - is short-hand for Response.Write(Server.HTMLEncode()) ASP.net 4.0+
<%#: %> - is used for data binding expressions and is automatically HTMLEncoded.
<%-- --%> - is for server-side comments
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Java: Literal percent sign in printf statement
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The percent sign is escaped using a percent sign:
System.out.printf("%s\t%s\t%1.2f%%\t%1.2f%%\...
MSTest copy file to test run folder
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edited Nov 22 '13 at 17:06
Richard Ev
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an...
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
() => ...
Question mark (?) in XML attributes for Android
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edited Aug 31 '12 at 10:16
ubershmekel
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SQLite - increase value by a certain number
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Sample 1 (for all rows):
UPDATE Products SET Price = Price + 50
Sample 2 (for a specific row...