In one of my Rails apps I needed to do a case statement for a search. SQL has a built in function for this fortunately.
CASE current_state
WHEN 'Created' THEN 1
WHEN 'In Progress' THEN 2
WHEN 'Completed' THEN 3
END
Some Rails examples
# Use the %q method to make the sql string more readable
Post.order(%q{
CASE current_state
WHEN 'Created' THEN 1
WHEN 'In Progress' THEN 2
WHEN 'Completed' THEN 3
END
})
# OR a more dynamic method
the_order = ['Created','In Progress','Completed']
the_sql = "CASE current_state"
the_order.each_with_index do |x,i|
the_sql += " WHEN #{x} THEN #{i}"
end
the_sql += " END"
Post.order(the_sql)
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