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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...t comment.
– Synesso
May 4 '15 at 0:32
1
@EricWang Thanks, Eric, you're right - I believe that th...
Mean per group in a data.frame [duplicate]
... 22 87
Cat 2 67 43
Cat 3 45 32', header=TRUE)
aggregate(d[, 3:4], list(d$Name), mean)
Group.1 Rate1 Rate2
1 Aira 16.33333 47.00000
2 Ben 31.33333 50.33333
3 Cat 44.66667 54.00000
Here we aggregate columns 3 and 4 of data.frame d, ...
Find where python is installed (if it isn't default dir)
....6.6 (r266:84297, Aug 24 2010, 18:13:38) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.executable
'c:\\Python26\\python.exe'
>>> sys.exec_prefix
'c:\\Python26'
>>>
>>> pr...
#if Not Debug in c#?
...
KhanZeeshanKhanZeeshan
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Is there a jQuery unfocus method?
...
RichieHindleRichieHindle
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xpath find if node exists
...
326
<xsl:if test="xpath-expression">...</xsl:if>
so for example
<xsl:if test="/h...
Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit
...amily
– nine stones
Feb 13 '14 at 5:32
...
Arrays, heap and stack and value types
...values of each of these types would require 16 bytes of memory (assuming a 32-bit word size). The field I in each case takes 4 bytes to store its value, the field S takes 4 bytes to store its reference, and the field L takes 8 bytes to store its value. So the memory for the value of both RefType a...
Forward function declarations in a Bash or a Shell script?
...|
edited Nov 27 '12 at 16:32
answered Nov 27 '12 at 16:19
J...
Get element at specified position - JavaScript
...day.
– Vlad Nicula
Jan 20 '15 at 14:32
I have tried this method and it measure the position according to the document....