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Combining INSERT INTO and WITH/CTE
...ions go at the top.
Wrapping every insert in a CTE has the benefit of visually segregating the query logic from the column mapping.
Spot the mistake:
WITH _INSERT_ AS (
SELECT
[BatchID] = blah
,[APartyNo] = blahblah
,[SourceRowID] = blahblahblah
FROM Table1 AS t1
)
INSERT ...
Difference between app.all('*') and app.use('/')
Is there a useful difference between app.all('*', ... ) and app.use('/', ...) in Node.JS Express?
7 Answers
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Pass ruby script file to rails console
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You can use
bundle exec rails runner "eval(File.read 'your_script.rb')"
UPDATE:
What we also have been using a lot lately is to load the rails environment from within the script itself. Consider doit.rb:
#!/usr/bin/env ruby
require "/path/to/rails_app/config/environment"
# ......
Why is String immutable in Java?
I was asked in an interview why String is immutable
12 Answers
12
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Should I use alias or alias_method?
I found a blog post on alias vs. alias_method . As shown in the example given in that blog post, I simply want to alias a method to another within the same class. Which should I use? I always see alias used, but someone told me alias_method is better.
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MySQL Cannot drop index needed in a foreign key constraint
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You have to drop the foreign key. Foreign keys in MySQL automatically create an index on the table (There was a SO Question on the topic).
ALTER TABLE mytable DROP FOREIGN KEY mytable_ibfk_1 ;
share
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Skip rows during csv import pandas
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^ No need to import at all, it is directly accessible as pd.compat.StringIO .
– cs95
Apr 8 '19 at 17:51
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Traits vs. interfaces
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Except that traits are not interfaces at all. Interfaces are specification that can be checked against. Traits cannot be checked against, hence they are implementation only. They are the exact opposite of interfaces. That line in the RFC is simply wrong...
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Create a menu Bar in WPF?
...nel>
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open"/>
<MenuItem Header="_Close"/>
<MenuItem Header="_Save"/>
</MenuItem>
</Menu>
<StackPanel></StackPa...
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/16ae3db5a5c6a08383b974ae...