Adding multiple times the same related issue relation is possible
#1 Updated by Etienne Massip over 10 years ago
- Subject changed from Adding multiple times the same related issue is possible to Adding multiple times the same related issue relation is possible
As explained in RoR documentation (both 2.3.x and 3.x, this excerpt is from 3.x'):
Concurrency and integrity Using this validation method in conjunction with ActiveRecord::Base#save does not guarantee the absence of duplicate record insertions, because uniqueness checks on the application level are inherently prone to race conditions. (...) This could even happen if you use transactions with the ‘serializable’ isolation level. The best way to work around this problem is to add a unique index to the database table using (...)#add_index. (...) The bundled ActiveRecord::ConnectionAdapters distinguish unique index constraint errors from other types of database errors by throwing an ActiveRecord::RecordNotUnique exception. For other adapters you will have to parse the (database-specific) exception message to detect such a case.
A simple migration creating an unique index on
issue_relation columns should do the job.