Active 3 years, 8 months ago. Viewed 4k times. Improve this question. Note that the setting spring. It will drop and recreate it only if you change the column type. Add a comment. Active Oldest Votes. Driver" ; properties. SQLServerDialect" ; if environment. Improve this answer. Martin Martin 1, 2 2 gold badges 23 23 silver badges 56 56 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook.
Sign up using Email and Password. We're a place where coders share, stay up-to-date and grow their careers. This article has been written for readers who have experience with Java , Hibernate and Spring Boot. All examples use MySql but you could also use other relational databases that you are comfortable with.
The Java ecosystem gives you a lot of tools to magically update your database schemas, but are all of these tools reliable enough to be used with a production database?
In this article - the first in a series - we will focus on industry best practices and Hibernate 's auto-schema generation feature. We will explain what we've learned from it and where it is suitable to be used. In a subsequent article, we will discuss how database schema changes can be made with a database migration tool such as Liquibase.
All code samples are available in our dedicated GitHub repository. Let's first create a new database schema called addressBook using the MySql command-line client:.
The configurations for MySql can be found inside application. The first 3 lines explain how to connect to MySql. Our password is hardcoded for simplicity's sake, but in real life we would store it in a secret. At this stage, our database schema has just been created. Our application only has a single entity class called User. At startup, Hibernate parses all classes that have been decorated with the Entity annotation. It then scans the User class and generates an SQL table creation query.
The table name, column names, types, and etc. The addressBook database schema has been generated and it contains the User table. When Hibernate runs the tests again, it compares the class User against the table user. It then sees that class and table are in sync and it does not make any further changes. While SQL looks similar when working with various database providers, there is no such thing as completely interoperable SQL.
There are subtle differences in how each SQL handles dates, string concatenation, etc. Now we are going to discuss HQL update, delete Queries. If we want to update the multiple records at a time, we can go with HQL update. Or else If our requirement is to update a single record then we can go with hibernate update query. To execute the non-select operations update, delete, insert also, we need to have the Hibernate Query object. By calling the executeUpdate method on query object, we can fire the HQL non-select commands.
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