Path: csiph.com!au2pb.net!feeder.erje.net!1.eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: Cecil Westerhof Newsgroups: comp.lang.java.programmer Subject: Re: Is it possible to use JPA and JDBC at the same time Date: Mon, 17 Aug 2015 08:24:04 +0200 Organization: Decebal Computing Lines: 27 Message-ID: <87mvxqsa9n.fsf@Equus.decebal.nl> References: <87vbcj3vja.fsf@Equus.decebal.nl> <55cd346e$0$304$14726298@news.sunsite.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: mx02.eternal-september.org; posting-host="528adfd6ad074c92fdc6a7f8fb9e23d8"; logging-data="829"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19U0fvotDbUYzCaS6KALwcBFmUJRdrTAiE=" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) Cancel-Lock: sha1:eyHi0rzj0qiVk1+lU+M3CgZxaHA= sha1:zCi/q247M5AQTlyK3JAHEZnQTZM= X-Homepage: http://www.decebal.nl/ Xref: csiph.com comp.lang.java.programmer:32333 On Friday 14 Aug 2015 02:21 CEST, Arne Vajhøj wrote: > On 8/13/2015 2:14 PM, Cecil Westerhof wrote: >> I am new to JPA and have to migrate an application from JDBC to >> JPA. There are quite some queries. Would it be possible to mix JDBC >> and JPA together? >> >> I would suppose not, but if it was possible, that would circumvent >> a big bang. > > The standard problems with using two persistence frameworks are > cache inconsistencies and transactional issues. > > I have not read the fine print in the JPA specs to say whether > this would be a problem for JPA and JDBC. > > But I would probably go for big bang JPA. Lower risk. And > with createNativeQuery you can execute SQL queries (so you > can reuse you existent SQL queries). I was afraid for that. ;-) There are a lot of queries. :-( But for testing purposes I could maybe do it class by class. -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof