In MySQL,
CopyCONCAT('foo', 'bar', NULL) = NULL
the NULL always wins. This is not true in PosgreSQL.
If you would rather treat NULL as an empty string, use CONCAT_WS (concatenation with separator) instead:
CopyCONCAT_WS('', 'foo', 'bar', NULL) = 'foobar'
By refactoring problematic code and creating automated tests, makandra can vastly improve the maintainability of your Rails application.
If you found our advice to be useful, you might like our book about maintainable Rails applications:
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