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Hibernate will not load all associated objects until they are needed – this is called lazy loading. The concept object above never dove into the concept_answer table to get the list of answers for concept 1234. If we had called concept.getConceptAnswers() Hibernate at that point would have made a call to the database to retrieve the answers for us. For this reason, you must either fetch/save/manipulate your object in the same session (between one open/closeSession) or you must hydrate all object collections in the object by calling the getters (getConceptAnswers, getConceptNames, getSynonyms, etc).

Liquibase

We use liquibase for database schema changes.

OpenMRS Source code

OpenMRS lives in a Git repository.  See the Code Repositories wiki page for more info.

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