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MySQL, update multiple tables with one query
I have a function that updates three tables, but I use three queries to perform this. I wish to use a more convenient approach for good practice.
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Random record in ActiveRecord
...ing ORDER BY RAND() or RANDOM() (depending on the database). It's not a performance issue if you don't have a performance issue.
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How do I associate a Vagrant project directory with an existing VirtualBox VM?
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WARNING: The solution below works for Vagrant 1.0.x but not Vagrant 1.1+.
Vagrant uses the ".vagrant" file in the same directory as your "Vagrantfile" to track the UUID of your VM. This file will not exist if a VM does not exist. The format of the file is JS...
SQL Server Insert if not exists
...S (@_DE, @_ASSUNTO, @_DATA)
END
END
Updated : (thanks to @Marc Durdin for pointing)
Note that under high load, this will still sometimes fail, because a second connection can pass the IF NOT EXISTS test before the first connection executes the INSERT, i.e. a race condition. See stackoverflow.c...
For each row return the column name of the largest value
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One option using your data (for future reference, use set.seed() to make examples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than usin...
How to change ProgressBar's progress indicator color in Android
...ndroid:id/background" and android:id="@android:id/secondaryProgress" stand for.
– RustamG
May 29 '17 at 7:00
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Programmatically update widget from activity/service/receiver
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DON'T follow @gelupa comment to use R.xml.mywidget for widgetID! It is COMPLETELY wrong and just cost me 4hours of debugging!!! USE MobileMon solution to get correct widgetID
– Ilja S.
Jun 11 '17 at 13:24
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How to express a NOT IN query with ActiveRecord/Rails?
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@danneu just swap .empty? for .blank? and you are nil-proof
– colllin
Feb 5 '13 at 0:57
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Should I make HTML Anchors with 'name' or 'id'?
...o the HTML 5 specification, 5.9.8 Navigating to a fragment identifier:
For HTML documents (and the text/html MIME type), the following processing model must be followed to determine what the indicated part of the document is.
Parse the URL, and let fragid be the <fragment> compo...
How to assign the output of a command to a Makefile variable
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Wrapping the assignment in an eval is working for me.
# dependency on .PHONY prevents Make from
# thinking there's `nothing to be done`
set_opts: .PHONY
$(eval DOCKER_OPTS = -v $(shell mktemp -d -p /scratch):/output)
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