Prevent duplicate entry for save smartly in grails

Question

I have a domain named thana where I put all the thanaName. But I don't want to save any duplicate name. There may be a lot of way for doing this but which will be much smarter I don't know. Can anyone please help me on this. any example or source code will do the work perfectly. thanks in advance for watching the question.

Answer 1

This sounds like the prefect use case for the unique constraint.

class MyDomain {
  String name
  OtherDomain related

  static constraints = {
    name unique: ['related'] // each instance must have a unique name per related
  }
}

Edit

Updated based on question in comment. The above will ensure that name is unique for each related. So, for example if MyDomain A has a related instance id of 1 and a name of "Test" no ohter instance of MyDomain with the same related instance can have the name of "Test". However, MyDomain B which has a rleated instance id of 2 can have a name of "Test" since the unique is per "related" in the above example.