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Rails: Adding an index after adding column
...able < ActiveRecord::Migration
def change
add_index :table, :user_id
end
end
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How to link to a named anchor in Multimarkdown?
...er to it on the same page by [link text](#abcd).
(This uses name= and not id=, for reasons explained in this answer.)
Remote references can use [link text](http://...#abcd) of course.
This works like a dream, provided you have control over the source and target texts. The anchor can even appear i...
Splitting string into multiple rows in Oracle
...i can you please clarify me why the above query gives duplicate rows if i didn't use distinct keyword in query
– Jagadeesh G
Sep 12 '13 at 16:50
2
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How to link a Facebook app with an existing fan page
... The key is making sure App Page is the ONLY category. We had "Video Game" and "App Page" and this didn't work until we removed "Video Game." As an aside Facebook's workflow is insane--almost like it was written by a 19-year-old in his dorm room.
– Mike Pandolfini
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Android getting value from selected radiobutton
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Tested and working. Check this
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android....
Best design for a changelog / auditing database table? [closed]
...rted from the very minimalistic design, like the one you described:
event ID
event date/time
event type
user ID
description
The idea was the same: to keep things simple.
However, it quickly became obvious that this minimalistic design was not sufficient. The typical audit was boiling down to qu...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...".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 JSON. It looks like this if a single VM exists:
{
"active":{
"default":"02f8b71c-75c6-4f33-a161-0f46a0665ab6"
}
}
defaul...
How to run an EXE file in PowerShell with parameters with spaces and quotes
...ync -source:dbfullsql="Data Source=mysource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;" -dest:dbfullsql="Data Source=.\mydestsource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;",computername=10.10.10.10,username=administrator,password=adminpass
Arg 0 is <-...
Is there a command to list all Unix group names? [closed]
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Yes MichaelIT is right the groups command did not list all groups. I asked this because unsure if there is a simple command like groups to lists all groups names or even a swith to it like groups [-a|--all] to list all system groups without doing file scan.
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WHERE vs HAVING
...level aliases in GROUP BY, ORDER BY and HAVING.
And are there any downsides instead of doing "WHERE 1" (writing the whole definition instead of a column name)
If your calculated expression does not contain any aggregates, putting it into the WHERE clause will most probably be more efficient.
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