Exception: ActiveRecord::UnknownAttributeReference
- Inherits:
 - 
      ActiveRecordError
      
        
- Object
 - StandardError
 - ActiveRecordError
 - ActiveRecord::UnknownAttributeReference
 
 
- Defined in:
 - lib/active_record/errors.rb
 
Overview
UnknownAttributeReference is raised when an unknown and potentially unsafe value is passed to a query method when allow_unsafe_raw_sql is set to :disabled. For example, passing a non column name value to a relation's #order method might cause this exception.
When working around this exception, caution should be taken to avoid SQL injection vulnerabilities when passing user-provided values to query methods. Known-safe values can be passed to query methods by wrapping them in Arel.sql.
For example, with allow_unsafe_raw_sql set to :disabled, the following code would raise this exception:
Post.order("length(title)").first
The desired result can be accomplished by wrapping the known-safe string in Arel.sql:
Post.order(Arel.sql("length(title)")).first
Again, such a workaround should not be used when passing user-provided values, such as request parameters or model attributes to query methods.