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PONamed scopes with inheritance in Rails 3 mapping to wrong table
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  1. PONamed scopes with inheritance in Rails 3 mapping to wrong table
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    copied!<p>I am attempting to use inheritance from a class which has a named scope:</p> <pre><code>Class A &lt; ActiveRecord::Base scope :useful_scope, lambda { |value1, value2| where(:value1 =&gt; value1, :value2 =&gt; value2) end end Class B &lt; A set_table_name "b" end </code></pre> <p>The problem I'm encountering is that the table name in the sql queries still reference Class A's Table:</p> <pre><code>A.useful_scope("alpha", "beta").to_sql =&gt; "SELECT \"a\".* FROM \"a\" WHERE \"a\".\"value1\" = 'alpha' AND \"a\".\"value2\" = 'beta'" B.useful_scope("alpha", "beta").to_sql =&gt; "SELECT \"b\".* FROM \"b\" WHERE \"a\".\"value1\" = 'alpha' AND \"a\".\"value2\" = 'beta'" </code></pre> <p>Note that the table names in the WHERE statement still refer to A. I am modifying an existing gem with various dependencies on the Class A scope throughout, so I need to maintain it's current syntax. I want to maintain the table name specifiers in the WHERE clause SQL to ensure that the scope will behave well when nested with other named scope definitions.</p> <p>I have tried the following:</p> <ul> <li>Using a lambda parameter for the table name. This broke the syntax for other references to the scope which only provided the current 2 properties.</li> <li>Using an abstract class to define the scope. The same binding of the table name occurred, but using the class name of the Abstract Class.</li> <li>Using a scope defined in a module and including the module. The same binding of the table name occurred.</li> </ul> <p>Is there a way that I can force the scope to be evaluated on each inherited class, so that it isn't explicitly mapped to the parent classes table?</p>
 

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