Comments on: Incremental schema upgrades using Hibernate http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/ A man needs a little madness, or else he never dares cut the rope and be free. -Nikos Kazantzakis Tue, 06 Jan 2009 21:44:04 +0000 http://wordpress.org/?v=2.2.1 By: Adam Monsen http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-131333 Adam Monsen Wed, 05 Nov 2008 21:01:57 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-131333 Excellent writeup, thanks! Might as well mention LiquiBase while I'm here. I haven't tried it, but it looks promising as a generic and feature-rich schema migration tool. Excellent writeup, thanks!

Might as well mention LiquiBase while I’m here. I haven’t tried it, but it looks promising as a generic and feature-rich schema migration tool.

]]> By: Tristan http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-117405 Tristan Sat, 13 Sep 2008 14:39:39 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-117405 Anyone know how to do this if you are using annotations? Then the multiple mappings file part doesn't make sense. I'm trying some things now. All I really want to do is add some persistent fields, not modify or delete any columns. Anyone know how to do this if you are using annotations? Then the multiple mappings file part doesn’t make sense. I’m trying some things now. All I really want to do is add some persistent fields, not modify or delete any columns.

]]> By: Daniel http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-7858 Daniel Fri, 08 Dec 2006 01:05:16 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-7858 Rachel, The primary benefit of using Hibernate is that it handles the slight variations between databases. There are not many, but enough to make life annoying if you are targetting multiple dbs. Certainly, Hibernate will not automatically change column names or handle some of the more interesting common data transformations. It would be very nice if it did, that may be something for the future. The way we handled it is with a mixture of the two approaches. We let hibernate handle all of the schema management since it is trivial for us to do so, and then if we need any added bits, we write some simple SQL that we are sure will work on different DBs. And in practice, we dont often end up with more than 2 or 3 .hbm.xml files per version. Your approach sounds like it works well for you. If you are happy to write the SQL, then it certainly does have advantages. Thanks for your comment. Rachel,

The primary benefit of using Hibernate is that it handles the slight variations between databases. There are not many, but enough to make life annoying if you are targetting multiple dbs.

Certainly, Hibernate will not automatically change column names or handle some of the more interesting common data transformations. It would be very nice if it did, that may be something for the future.

The way we handled it is with a mixture of the two approaches. We let hibernate handle all of the schema management since it is trivial for us to do so, and then if we need any added bits, we write some simple SQL that we are sure will work on different DBs. And in practice, we dont often end up with more than 2 or 3 .hbm.xml files per version.

Your approach sounds like it works well for you. If you are happy to write the SQL, then it certainly does have advantages.

Thanks for your comment.

]]> By: Rachel McConnell http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-7823 Rachel McConnell Thu, 07 Dec 2006 17:23:00 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-7823 I currently handle schema updates with a custom process I wrote that uses a similar process to Rails: one initial schema.sql file, plus one 00X_update.sql file per schema version. It looks like using Hibernate's method would trade in my one file per version for N files per version, one for each object whose interface changed, and not even let me do things like rename columns much less drop or change constraints or do data transformations. I have to say I'm not sold on it! I currently handle schema updates with a custom process I wrote that uses a similar process to Rails: one initial schema.sql file, plus one 00X_update.sql file per schema version. It looks like using Hibernate’s method would trade in my one file per version for N files per version, one for each object whose interface changed, and not even let me do things like rename columns much less drop or change constraints or do data transformations. I have to say I’m not sold on it!

]]> By: SQL schema upgrades a thing of the past? http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-2929 SQL schema upgrades a thing of the past? Tue, 17 Oct 2006 11:37:59 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-2929 [...] I consider Schema migration to be one of the more tedious and yet non-trivial tasks that is required by any application that employs relational persistence. Yes, Hibernate makes this task somewhat easier to deal with. However, even with Hibernate, you will still need to roll up your sleeves and write some SQL to handle the migration of the data. [...] […] I consider Schema migration to be one of the more tedious and yet non-trivial tasks that is required by any application that employs relational persistence. Yes, Hibernate makes this task somewhat easier to deal with. However, even with Hibernate, you will still need to roll up your sleeves and write some SQL to handle the migration of the data. […]

]]> By: Tom http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-1431 Tom Mon, 28 Aug 2006 19:02:13 +0000 http://www.alittlemadness.com/2006/08/28/incremental-schema-upgrades-using-hibernate/#comment-1431 Thanks for the info. Thanks for the info.

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