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Is there a regular expression to detect a valid regular expression?
Is it possible to detect a valid regular expression with another regular expression? If so please give example code below.
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How to add column if not exists on PostgreSQL?
Question is simple. How to add column x to table y , but only when x column doesn't exist ? I found only solution here how to check if column exists.
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Spring Data JPA find by embedded object property
...ce method signature that will let me find entities with a property of an embedded object in that entity. Does anyone know if this is possible, and if so how?
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Java multiline string
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Stephen Colebourne has created a proposal for adding multi-line strings in Java 7.
Also, Groovy already has support for multi-line strings.
share
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Run a callback only if an attribute has changed in Rails
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Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c...
What is the python “with” statement designed for?
I came across the Python with statement for the first time today. I've been using Python lightly for several months and didn't even know of its existence! Given its somewhat obscure status, I thought it would be worth asking:
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Remove leading or trailing spaces in an entire column of data
...:
+----+------------+---------------------+
| | A | B |
+----+------------+---------------------+
| 1 | =TRIM(B1) | value to trim here |
+----+------------+---------------------+
So to do the whole column...
1) Insert a column
2) Insert TRIM function pointed at ce...
What's an Aggregate Root?
.... The central concept of an Aggregate Root keeps coming up. When searching both the web and Stack Overflow for help with what an aggregate root is, I keep finding discussions about them and dead links to pages that are supposed to contain base definitions.
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How do I strip non alphanumeric characters from a string and keep spaces?
I want to create a regex that removes all non-alphanumber characters but keeps spaces. This is to clean search input before it hits the db. Here's what I have so far:
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How do you run NUnit tests from Jenkins?
...s:
Add the NUnit Plugin to Jenkins
In your project go to Configure -> Build -> Add a build step
In the dropdown scroll down to -> Execute Windows Batch Command
Ensure this step is placed after your MSBuild step
Add the following, replacing the variables:
Single dll test:
[PathToNUn...