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How can I join elements of an array in Bash?
...e Bash function that supports multi-character delimiters is:
function join_by { local d=$1; shift; local f=$1; shift; printf %s "$f" "${@/#/$d}"; }
For example,
join_by , a b c #a,b,c
join_by ' , ' a b c #a , b , c
join_by ')|(' a b c #a)|(b)|(c
join_by ' %s ' a b c #a %s b %s c
join_by $'\n' a b c...
How to delete the top 1000 rows from a table using Sql Server 2008?
...
The code you tried is in fact two statements. A DELETE followed by a SELECT.
You don't define TOP as ordered by what.
For a specific ordering criteria deleting from a CTE or similar table expression is the most efficient way.
;WITH CTE AS
(
SELECT TOP 1000 *
FROM [mytab]
ORDER BY a1
)
...
PostgreSQL - how to quickly drop a user with existing privileges
... its ownership to other roles (or drop the object).
This is best achieved by
REASSIGN OWNED BY <olduser> TO <newuser>
and
DROP OWNED BY <olduser>
The latter will remove any privileges granted to the user.
See the postgres docs for DROP ROLE and the more detailed description...
SQL multiple column ordering
I am trying to sort by multiple columns in SQL, and in different directions. column1 would be sorted descending, and column2 ascending.
...
Difference between CLOCK_REALTIME and CLOCK_MONOTONIC?
... difference between CLOCK_REALTIME and CLOCK_MONOTONIC clocks returned by clock_gettime() on Linux?
7 Answers
...
How to find and return a duplicate value in array
...irst option being the fastest:
ary = ["A", "B", "C", "B", "A"]
ary.group_by{ |e| e }.select { |k, v| v.size > 1 }.map(&:first)
ary.sort.chunk{ |e| e }.select { |e, chunk| chunk.size > 1 }.map(&:first)
And a O(N^2) option (i.e. less efficient):
ary.select{ |e| ary.count(e) > 1 ...
How to filter Android logcat by application? [duplicate]
How can I filter Android logcat output by application? I need this because when I attach a device, I can't find the output I want due to spam from other processes.
...
Sorting arrays in NumPy by column
How can I sort an array in NumPy by the nth column?
13 Answers
13
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Linear Regression and group by in R
...to a vector. That does not seem very R-like, however. In SAS I would do a 'by' statement and in SQL I would do a 'group by'. What's the R way of doing this?
...
Get JSF managed bean by name in any Servlet related class
...vlet (for AJAX/JSON) in which I would like to reference my @ManagedBeans by name. I'm hoping to map:
6 Answers
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