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Want to find records with no associated records in Rails
...s => { :id => nil } )
Update 3 - Rails 5
Thanks to @Anson for the excellent Rails 5 solution (give him some +1s for his answer below), you can use left_outer_joins to avoid loading the association:
Person.left_outer_joins(:contacts).where( contacts: { id: nil } )
I've included it here so...
What are '$$' used for in PL/pgSQL
...th single quotes in PostgreSQL
As to your second question:
Read the most excellent manual on CREATE FUNCTION to understand the last line of your example.
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MySQL connection not working: 2002 No such file or directory
...TP and custom installation of MySQL.
The answer is based on @alec-gorge's excellent response, but since I had to google some specific changes to have it configured in my configuration, mostly Mac OS X-specific, I thought I'd add it here for the sake of completeness.
Enable PHP5 support for Apache ...
ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
...10.000.000 + of MySql records and 10+ different database .
It has got very excellent support for MySQL and high performance on indexing , research is fast but maybe a little less than Lucene.
However it's the right choice if you need quickly indexing every day and use a MySQL db.
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Best practices for overriding isEqual: and hash
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+1 Excellent answer, deserves more upvotes, especially since he actually talks about "best practices" and the theory behind why a good (unique) hash is important.
– Quinn Taylor
Jul 11 '09 ...
Android - Writing a custom (compound) component
...ooking for. Amazing how such a long question can have such a short answer. Excellent!
– Tom van Zummeren
Sep 25 '09 at 11:27
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What should every JavaScript programmer know? [closed]
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+1 Keep forgetting about that book, excellent recommendation.
– David
Apr 13 '10 at 10:43
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How to run Maven from another directory (without cd to project dir)?
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Excellent. mvn -f param doesn't work with multimodule projects using relative path to reference the child poms. Thanks, that's what I was looking for.
– redochka
Apr 11 '15 at 16:08
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How to pass variable from jade template file to a script file?
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Excellent answer! I've been searching this subject for 20+ minutes and no other answers stated the difference between !{} and #{}. This whole time I just thought !{] was the deprecated equivalent of #{}... Thanks again.
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Gulp.js task, return on src?
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Excellent! thanks for the reply Sindre. Have gulp running like a charm now. Love it.
– boldfacedesignuk
Feb 16 '14 at 21:08
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