From open-jpa-dev-return-3065-apmail-incubator-open-jpa-dev-archive=incubator.apache.org@incubator.apache.org Tue Apr 03 01:47:05 2007 Return-Path: Delivered-To: apmail-incubator-open-jpa-dev-archive@locus.apache.org Received: (qmail 30024 invoked from network); 3 Apr 2007 01:47:04 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.2) by minotaur.apache.org with SMTP; 3 Apr 2007 01:47:04 -0000 Received: (qmail 36687 invoked by uid 500); 3 Apr 2007 01:47:11 -0000 Delivered-To: apmail-incubator-open-jpa-dev-archive@incubator.apache.org Received: (qmail 36662 invoked by uid 500); 3 Apr 2007 01:47:11 -0000 Mailing-List: contact open-jpa-dev-help@incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: open-jpa-dev@incubator.apache.org Delivered-To: mailing list open-jpa-dev@incubator.apache.org Received: (qmail 36653 invoked by uid 99); 3 Apr 2007 01:47:11 -0000 Received: from herse.apache.org (HELO herse.apache.org) (140.211.11.133) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 02 Apr 2007 18:47:11 -0700 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=UNPARSEABLE_RELAY X-Spam-Check-By: apache.org Received-SPF: pass (herse.apache.org: local policy) Received: from [192.18.42.249] (HELO nwk-ea-fw-1.sun.com) (192.18.42.249) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 02 Apr 2007 18:47:03 -0700 Received: from d1-sfbay-09.sun.com ([192.18.39.119]) by nwk-ea-fw-1.sun.com (8.13.6+Sun/8.12.9) with ESMTP id l331khKN023942 for ; Mon, 2 Apr 2007 18:46:43 -0700 (PDT) Received: from conversion-daemon.d1-sfbay-09.sun.com by d1-sfbay-09.sun.com (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) id <0JFW00501FLAEI00@d1-sfbay-09.sun.com> (original mail from Marina.Vatkina@Sun.COM) for open-jpa-dev@incubator.apache.org; Mon, 02 Apr 2007 18:46:42 -0700 (PDT) Received: from [129.145.132.161] by d1-sfbay-09.sun.com (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPSA id <0JFW007TDFLU2B0T@d1-sfbay-09.sun.com> for open-jpa-dev@incubator.apache.org; Mon, 02 Apr 2007 18:46:42 -0700 (PDT) Date: Mon, 02 Apr 2007 18:46:30 -0700 From: Marina Vatkina Subject: Re: Using DDL generation in a Java EE environment? In-reply-to: Sender: Marina.Vatkina@Sun.COM To: open-jpa-dev@incubator.apache.org Reply-to: Marina.Vatkina@Sun.COM Message-id: <4611B1F6.1070407@Sun.COM> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=us-ascii Content-transfer-encoding: 7BIT X-Accept-Language: en-us, en References: <45F9DE3C.5020202@sun.com> <49F3A300-9A8C-433F-99D3-845F41C2E6F8@apache.org> <460067EB.8050403@sun.com> <46006BFB.3080608@sun.com> <8C61F808-2A12-4379-8297-5A9008262193@apache.org> <46007557.2050102@sun.com> <46008275.4020308@sun.com> <460C1F13.4040101@sun.com> <41680D91-1D8C-490D-A529-83A793D0DEC6@apache.org> <460D705F.6080605@sun.com> User-Agent: Mozilla/5.0 (X11; U; SunOS i86pc; en-US; rv:1.7) Gecko/20051027 X-Virus-Checked: Checked by ClamAV on apache.org Marc, All my experiments are just that - experiments. My goal is to enable DDL generation in GlassFish when the persistence provider is set to that of the OpenJPA and the user-visible behavior is similar to the one we have for CMP (i.e. our internal code) and for TopLink Essentials as the persistence provider. Foe now I'm exploring my options. I'm using example (I started with the EE version, and now switched to the SE version) from the GlassFish persistence example page (https://glassfish.dev.java.net/javaee5/persistence/persistence-example.html). The example has 2 entities, Customer and Order, and 1ToMany relationship between them. Of course, I'm slightly modifying persistence.xml to make it work with the OpenJPA. In one of my experiments I created a customer table with columns A and B, A being a PK before running the mapping tool. Mapping tool results were a bit surprising ;). thanks, -marina Marc Prud'hommeaux wrote: > > On Mar 30, 2007, at 4:17 PM, Marina Vatkina wrote: > >> Marc, >> >> I'd rather have provider-neutral code in GlassFish ;(. > > > Well, until the JPA spec (or some other spec) provides details on how > schema creation and/or migration should work, I don't think it is > realistic to expect every vendor to behave in exactly the same way > w.r.t. how their schema manipulation tools work. We're always open to > specific suggestions for how to improve how our operate, though. > > >> The problem with adding new columns to the existing table in my >> example below is a) in having a PK in the table that is not mapped to >> any field the entity, and b) not making the entity's id a pk (I >> didn't get any warning from not being able to add or create a PK - >> does OpenJPA suppress them?). > > > I don't really understand. Are you saying you want to map to a table > that has a primary key, but you don't want to map any field in your > entity to that primary key? Is that is the case, how do you expect > primary key generation to work? > > I wouldn't be surprised, however, if we don't actually validate that > what you declare to be a primary key in your entity is actually defined > as a primary key in the database. We don't require that the column > actually be declared to be a primary key in order for OpenJPA to work > correctly (although I can't envision any reason why you wouldn't want > to make it a proper primary key). > > >> thanks, >> -marina >> >> Marc Prud'hommeaux wrote: >> >>> Marina- >>> The problem is that OpenJPA just ignores extra, unmapped columns. >>> Since we don't require that you map all of the columns of a >>> database table to an entity, tables can exist that have unmapped >>> columns. By default, we tend to err on the side of caution, so we >>> never drop tables or columns. The "deleteTableContents" flag merely >>> deletes all the rows in a table, it doesn't actually drop the table. >>> We don't have any options for asserting that the table is mapped >>> completely. That might be a nice enhancement, and would allows >>> OpenJPA to warn when it sees a existing table with unmapped columns. >>> You could manually drop the tables using the mappingtool by >>> specifying the "schemaAction" argument to "drop", but there's no >>> way to do it automatically using the SynchronizeMappings. Note that >>> there is nothing preventing you from manually invoking the >>> MappingTool class from any startup to glue code that you want. >>> On Mar 29, 2007, at 4:18 PM, Marina Vatkina wrote: >>> >>>> Marc, Patrick, >>>> >>>> I didn't look into the file story yet, but what I've seen as the >>>> result of using >>>> >>>> >>> value="buildSchema >>>> (SchemaAction='add,deleteTableContents')"/> >>>> >>>> looks surprising: if I have there is an entity Foo with >>>> persistence fields 'x' and 'y' and a table FOO already exists in >>>> the database with columns A and B (there are no fields 'a' and 'b' >>>> in the entity), the table is not recreated, but the columns X and >>>> Y are added to the table FOO. The 'deleteTableContents' doesn't >>>> affect this behavior. >>>> >>>> Is it an expected behavior? >>>> >>>> What should I use to either create the table properly or get a >>>> message that such table already exist (and as in my case doesn't >>>> match the entity)? >>>> >>>> thanks, >>>> -marina >>>> >>>> Marina Vatkina wrote: >>>> >>>>> Then I'll first start with an easier task - check what happens in >>>>> EE if entities are not explicitly listed in the persistence.xml >>>>> file :). >>>>> thanks, >>>>> -marina >>>>> Marc Prud'hommeaux wrote: >>>>> >>>>>> Marina- >>>>>> >>>>>>> Let me give it a try. How would the persistence.xml property >>>>>>> look like to generate .sql file? >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> Actually, I just took a look at this, and it look like it isn't >>>>>> possible to use the "SynchronizeMappings" property to >>>>>> automatically output a sql file. The reason is that the >>>>>> property takes a standard OpenJPA plugin string that configures >>>>>> an instances of MappingTool, but the MappingTool class doesn't >>>>>> have a setter for the SQL file to write out to. >>>>>> >>>>>> So I think your only recourse would be to write your own adapter >>>>>> to to this that manually creates a MappingTool instance and >>>>>> runs it with the correct flags for outputting a sql file. Take >>>>>> a look at the javadocs for the MappingTool to get started, and >>>>>> let us know if you have any questions about proceeding. >>>>>> >>>>>> >>>>>> >>>>>> On Mar 20, 2007, at 4:59 PM, Marina Vatkina wrote: >>>>>> >>>>>>> Marc, >>>>>>> >>>>>>> Marc Prud'hommeaux wrote: >>>>>>> >>>>>>>> Marina- >>>>>>>> >>>>>>>>> They do in SE, but as there is no requirement to do it in >>>>>>>>> EE, people try to reduce the amount of typing ;). >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Hmm ... we might not actually require it in EE, since we do >>>>>>>> examine the ejb jar to look for persistent classes. I'm not >>>>>>>> sure though. >>>>>>>> You should test with both listing them and not listing them. >>>>>>>> I'd be interested to know if it works without. >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> Let me give it a try. How would the persistence.xml property >>>>>>> look like to generate .sql file? Where will it be placed in >>>>>>> EE environment? Does it use use the name as-is or prepend it >>>>>>> with some path? >>>>>>> >>>>>>> thanks. >>>>>>> >>>>>>>> On Mar 20, 2007, at 4:19 PM, Marina Vatkina wrote: >>>>>>>> >>>>>>>>> Marc, >>>>>>>>> >>>>>>>>> Marc Prud'hommeaux wrote: >>>>>>>>> >>>>>>>>>> Marina- >>>>>>>>>> On Mar 20, 2007, at 4:02 PM, Marina Vatkina wrote: >>>>>>>>>> >>>>>>>>>>> Marc, >>>>>>>>>>> >>>>>>>>>>> Thanks for the pointers. Can you please answer the >>>>>>>>>>> following set of questions? >>>>>>>>>>> >>>>>>>>>>> 1. The doc requires that "In order to enable automatic >>>>>>>>>>> runtime mapping, you must first list all your persistent >>>>>>>>>>> classes". Is this true for EE case also? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Yes. People usually list them all in the tags in >>>>>>>>>> the persistence.xml file. >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> They do in SE, but as there is no requirement to do it in >>>>>>>>> EE, people try to reduce the amount of typing ;). >>>>>>>>> >>>>>>>>> If OpenJPA can identify all entities in EE world, why can't >>>>>>>>> it do the same for the schema generation? >>>>>>>>> >>>>>>>>> I'll check the rest. >>>>>>>>> >>>>>>>>> thanks, >>>>>>>>> -marina >>>>>>>>> >>>>>>>>>>> 2. Section "1.2.Generating DDL SQL" talks about .sql >>>>>>>>>>> files, but what I am looking for are "jdbc" files, i.e. >>>>>>>>>>> files with the lines that can be used directly as >>>>>>>>>>> java.sql statements to be executed against database. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> The output should be sufficient. Try it out and see if the >>>>>>>>>> format is something you can use. >>>>>>>>>> >>>>>>>>>>> 3. Is there a document that describes all possible values >>>>>>>>>>> for the "openjpa.jdbc.SynchronizeMappings" property? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Unfortunately, no. Basically, the setting of the >>>>>>>>>> "SynchronizeMappings" property will be of the form "action >>>>>>>>>> (Bean1=value1,Bean2=value2)", where the "bean" values are >>>>>>>>>> those listed in org.apache.openjpa.jdbc.meta.MappingTool >>>>>>>>>> (whose javadoc you can see http://incubator.apache.org/ >>>>>>>>>> openjpa/ docs/ latest/ javadoc/org/ >>>>>>>>>> apache/openjpa/jdbc/meta/ MappingTool.html ). >>>>>>>>>> >>>>>>>>>>> thank you, >>>>>>>>>>> -marina >>>>>>>>>>> >>>>>>>>>>> Marc Prud'hommeaux wrote: >>>>>>>>>>> >>>>>>>>>>>> Marina- >>>>>>>>>>>> On Mar 15, 2007, at 5:01 PM, Marina Vatkina wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi, >>>>>>>>>>>>> >>>>>>>>>>>>> I am part of the GlassFish persistence team and was >>>>>>>>>>>>> wondering how does OpenJPA support JPA auto DDL >>>>>>>>>>>>> generation (we call it "java2db") in a Java EE >>>>>>>>>>>>> application server. >>>>>>>>>>>>> >>>>>>>>>>>>> Our application server supports java2db via creating two >>>>>>>>>>>>> sets of files for each PU: a ...dropDDL.jdbc and a >>>>>>>>>>>>> ...createDDL.jdbc file on deploy (i.e. before the >>>>>>>>>>>>> application is actually loaded into the container) >>>>>>>>>>>>> and then executing 'create' file as the last step >>>>>>>>>>>>> in deployment, and 'drop' file on undeploy or the 1st >>>>>>>>>>>>> step in redeploy. This allows us to drop tables >>>>>>>>>>>>> created by the previous deploy operation. >>>>>>>>>>>>> >>>>>>>>>>>>> This approach is done for both, the CMP and the default >>>>>>>>>>>>> JPA provider. It would be nice to add java2db support >>>>>>>>>>>>> for OpenJPA as well, and I'm wondering if we need to >>>>>>>>>>>>> do anything special, or it'll all work just by itself? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> We do have support for runtime creation of the schema via >>>>>>>>>>>> the "openjpa.jdbc.SynchronizeMappings" property. It is >>>>>>>>>>>> described at: >>>>>>>>>>>> http://incubator.apache.org/openjpa/docs/latest/ >>>>>>>>>>>> manual/ manual.html#ref_guide_mapping_synch >>>>>>>>>>>> The property can be configured to run the mappingtool >>>>>>>>>>>> (also described in the documentation) at runtime >>>>>>>>>>>> against all the registered persistent classes. >>>>>>>>>>>> >>>>>>>>>>>>> Here are my 1st set of questions: >>>>>>>>>>>>> >>>>>>>>>>>>> 1. Which API would trigger the process, assuming the >>>>>>>>>>>>> correct values are specified in the persistence.xml >>>>>>>>>>>>> file? Is it: >>>>>>>>>>>>> a) .createContainerEntityManagerFactory(...)? or >>>>>>>>>>>>> b) the 1st call to emf.createEntityManager() in this VM? >>>>>>>>>>>>> c) something else? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> b >>>>>>>>>>>> >>>>>>>>>>>>> 2. How would a user drop the tables in such environment? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> I don't think it can be used to automatically drop then >>>>>>>>>>>> create tables. The "mappingtool" can be executed >>>>>>>>>>>> manually twice, the first time to drop all the tables, >>>>>>>>>>>> and the second time to re- create them, but I don't >>>>>>>>>>>> think it can be automatically done at runtime with >>>>>>>>>>>> the "SynchronizeMappings" property. >>>>>>>>>>>> >>>>>>>>>>>>> 3. If the answer to either 1a or 1b is yes, how does the >>>>>>>>>>>>> code distinguish between the server startup time and >>>>>>>>>>>>> the application being loaded for the 1st time? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> That is one of the reasons why we think it would be >>>>>>>>>>>> inadvisable to automatically drop tables at runtime :) >>>>>>>>>>>> >>>>>>>>>>>>> 4. Is there a mode that allows creating a file with the >>>>>>>>>>>>> jdbc statements to create or drop the tables and >>>>>>>>>>>>> constraints? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Yes. See: >>>>>>>>>>>> http://incubator.apache.org/openjpa/docs/latest/ >>>>>>>>>>>> manual/ manual.html#ref_guide_ddl_examples >>>>>>>>>>>> >>>>>>>>>>>>> thank you, >>>>>>>>>>>>> -marina >>>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>> >>>>>>> >>>>>> >>>> >> >