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Convert column classes in data.table
...sing lapply and as.character:
dtnew <- dt[, lapply(.SD, as.character), by=ID]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : chr "1.487145280568" "-0.82...
How do I get a YouTube video thumbnail from the YouTube API?
...nformation Generator tool to get all
the information about a YouTube video by submitting a URL or video id.
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Can you pass parameters to an AngularJS controller on creation?
... services called 'name' and 'id'. The injector takes care of matching them by name during construction. See: the Value Recipe section of docs.angularjs.org/guide/providers
– Todd
Jun 15 '14 at 20:08
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Rails auto-assigning id that already exists
...ce!(t)
end
I found the reset_pk_sequence! from this thread. http://www.ruby-forum.com/topic/64428
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How do I UPDATE from a SELECT in SQL Server?
...
By far the simplest! However your missing the ID field from the inner SELECT. You'll need this for the WHERE clause to work
– John Doherty
Oct 31 '14 at 18:03
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Where can I find the IIS logs?
...lieve the latter path (...\HTTPERR) is the place where log files generated by http.sys land by default, not log files from IIS itself. See: technet.microsoft.com/en-us/library/cc784703%28v=ws.10%29.aspx
– Jon Schneider
Jan 5 '16 at 22:07
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Postgresql GROUP_CONCAT equivalent?
...ld, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifications, below).
Prior to version 8.4, you have to define it yourself prior to use:
CREATE AGGREGATE array_agg (anyeleme...
Remove Identity from a column in a table
...orer > Scripting > Table and view options > Script indexes (False by default)
– user423430
Nov 15 '16 at 23:58
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What is a Proxy in Doctrine 2?
...n't use proxy objects at all. They can be treated as internal objects used by Doctrine.
Why the lazy loading can't be implemented in the Entitiy itself?
Technically it could be but take a look at some random proxy object's class. It's full of dirty code, ugh. It's nice to have a clean code in ...
Delete duplicate rows from small table
...ING (
SELECT MIN(ctid) as ctid, key
FROM dups
GROUP BY key HAVING COUNT(*) > 1
) b
WHERE a.key = b.key
AND a.ctid <> b.ctid
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