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hasMany Considered Harmful



In 2010 I presented a talk at SpringOne/2GX on mapped collections in Grails (, pointing out potentially significant performance problems when using them and presenting simple alternative approaches for working with one-many and many-many relationships. In the many years since then I have often referenced this talk because the problems I pointed out are just as relevant today as they were back then. In this talk I'll revisit those ideas with updated code and information and encourage you to stop using hasMany and mapped collections in your Grails applications to avoid unintentionally hurting the performance of your applications.


50 min