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Add a default value to a column through a migration
...t; false
But some databases, like PostgreSQL, will not update the field for rows previously created, so make sure you update the field manaully on the migration too.
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Using Regular Expressions to Extract a Value in Java
I have several strings in the rough form:
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How can I add a column that doesn't allow nulls in a Postgresql database?
...LL" column to my Postgresql database using the following query (sanitized for the Internet):
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Change private static final field using Java reflection
I have a class with a private static final field that, unfortunately, I need to change it at run-time.
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Why should I avoid multiple inheritance in C++?
Is it a good concept to use multiple inheritance or can I do other things instead?
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How to find out which package version is loaded in R?
...to accomplish that.
> sessionInfo()
R version 2.15.0 (2012-03-30)
Platform: x86_64-pc-linux-gnu (64-bit)
locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C LC_TIME=en_US.UTF-8 LC_COLLATE=en_US.UTF-8
[5] LC_MONETARY=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8 LC_PAPER=C...
What do the following phrases mean in C++: zero-, default- and value-initialization?
...nitialization' is new with the C++ 2003 standard - it doesn't exist in the original 1998 standard (I think it might be the only difference that's more than a clarification). See Kirill V. Lyadvinsky's answer for the definitions straight from the standard.
See this previous answer about the behavio...
Bootstrap right Column on top on mobile view
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Use Column ordering to accomplish this.
col-md-push-6 will "push" the column to the right 6 and col-md-pull-6 will "pull" the column to the left on "md" or greater view-ports. On any smaller view-ports the columns will be in normal or...
How do I get the current line number?
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In .NET 4.5 / C# 5, you can get the compiler to do this work for you, by writing a utility method that uses the new caller attributes:
using System.Runtime.CompilerServices;
static void SomeMethodSomewhere()
{
ShowMessage("Boo");
}
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static void ShowMessage(string message,
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How to update a single library with Composer?
I need to install only 1 package for my SF2 distribution (DoctrineFixtures).
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