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Rails: How can I set default values in ActiveRecord?
...st this case like so:
self.number ||= 0.0 if self.has_attribute? :number
and for a boolean column...
self.bool_field = true if (self.has_attribute? :bool_value) && self.bool_field.nil?
Also note that the syntax is different prior to Rails 3.2 (see Cliff Darling's comment below)
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Using pg_dump to only get insert statements from one table within database
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The -d and -D options were removed from PostgreSQL 8.4 (see 8.4.0 release notes). You must now use the "long" names: pg_dump --column-inserts --data-only --table=<table> <database>
– Matthew Wood
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Why doesn't Dictionary have AddRange?
... because no one ever designed, specified, implemented, tested, documented and shipped that feature. - @Gabe Moothart
As to why? Well, likely because the behavior of merging dictionaries can't be reasoned about in a manner that fits with the Framework guidelines.
AddRange doesn't exist because a ...
Is there a way to do method overloading in TypeScript?
...cation, TypeScript does support method overloading, but it's quite awkward and includes a lot of manual work checking types of parameters. I think it's mostly because the closest you can get to method overloading in plain JavaScript includes that checking too and TypeScript tries to not modify actua...
How to configure encoding in Maven?
...default. So I added the property as a child element of the project element and everything is fine now:
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
&lt...
Creating a new directory in C
... directory; if that directory does not exist then it creates the directory and a log file inside of it, but if the directory already exists, then it just creates a new log file in that folder.
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How do I modify a MySQL column to allow NULL?
...ge case which is the TIMESTAMP type, which depending on your MySQL version and config can be NOT NULL specifying NULL as suggested by @ConroyP is more correct.
– Matthew Buckett
Jan 26 '16 at 13:37
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Cutting the videos based on start and end time using ffmpeg
I tried to cut the video using the start and end time of the video by using the following command
9 Answers
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PermGen elimination in JDK 8
I have installed JDK 8 and trying to run Eclipse. I am getting following warning message:
6 Answers
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How to create a new java.io.File in memory?
...tion then, is “it’s not possible”. This answer tries to be pragmatic and tell what the user could do instead. Andreas’ answer is clearly more thorough and a better (attempt at an) answer.
– haraldK
Jan 17 at 12:11
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