INFO 6250 Lecture Notes - Lecture 21: Lazy Initialization, Jquery, Rds-1
17 Mar 2016
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Info 6250 - lecture 21 - collections and entities in hibernate. Denormalization issue is resolved but delete anomaly is still there as below. cid coursename. So we need to have 2 tables in order to prevent multiple reference values for a single entity Another table will be a link table as below. Hibernate lazily loads collections and entities by default. Lazy fetching decides whether to load child objects while loading the parent object. You need to do this setting respective hibernate mapping file of the parent class. Lazy = true (means not to load child) by default the lazy loading of the child objects is true. There is a popular exception which a lot of hibernate newbees encounter. In order to prevent this exception you need to understand the concept of lazy initialization: when hibernate reads data from the database, the data is hold in the session.
