So because of this, Hibernate doesn’t massage the data for you, it just returns exactly what it got from the database. So what happens when you run a query that joins to the LoginHistory table? Well it will return as many rows as there are entries for that User in the LoginHistory table.

You’ll have a situation where you have many records in the LoginHistory table. And let’s say our user has logged in many times. When you have a base object, like say User and it joins to another table/object in an optional One-to-Many or optional Many-to-Many format, then you may get duplicates.Ĭonsider this scenario… A User objects joins to the LoginHistory object, which keeps track of all the times a particular User has logged into the system. You see the problem is typically caused by having left joins (or optional joins) in your objects. If you’re executing a query and finding that you have a bunch of duplicate records and haven’t a clue why, then you’re in the right place. This problem was the bane of my existence when I first started using Hibernate because I had no idea where the problem was coming from. How to Fix Duplicate Data from Hibernate Queries It is a 6 month, part-time, online Bootcamp that teaches you everything you need to know to get a job as a Java developer in the real-world. I'm now accepting students into an immersive programming Bootcamp where I guarantee you a job offer upon graduation. Interested in starting your coding career?

If you'd like to get in touch with Dustin, feel free to add him via LinkedIn here We'll also learn about the important lessons that Dustin learned once he began his job search, and what mistakes he was making early on before he pivoted his approach, which then lead to the job that he was offered. Ultimately we know how his story turned out, but in this special interview we'll learn about HOW he was able to accomplish the task of completing the Bootcamp and landing a job while also being a father of a 2 year old, a husband, a full-time employee and part-time college student. In this episode we'll talk to Dustin, who is a recent graduate from the Coders Campus Bootcamp and managed to land a job within two months of starting the search.ĭustin and I talk about his prior coding experience that he had before he joined our Bootcamp (spoiler: it wasn't much at all), and we talk about his experience as he went through the curriculum.

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