Thanks, Vlad
On Wed, May 10, 2017 at 7:07 PM, Milo van der Zee <m...@vanderzee.org> wrote: > Finally done... See https://github.com/hibernate/hibernate-orm/pull/1906 > > MAG, > Milo > > > > On 01/09/2017 01:02 PM, Vlad Mihalcea wrote: > > Thanks, > > Please send a Pull Request with a replicating test case. > > Vlad > > On Wed, Dec 28, 2016 at 12:05 AM, Milo van der Zee <m...@vanderzee.org> > wrote: > >> Hello all, >> >> During development of applications I'm used to set the schema creation >> to 'update' (hbm2ddl.auto = update). This makes life a bit easier. >> Issue with the newer version of Hibernate is that the name of the >> generated keys changed and so all keys are regenerated. For the large >> databases I use this takes hours and has to be done every time a fresh >> copy from production is taken to the development environment. >> >> I do use meaningful names for the indexes where possible. But when using >> abstract classes used by the entities that is not possible because the >> same fields from the abstract are used by many entity classes and so >> would end up having the same index names. >> >> I checked the code that decides if the index needs to be created and >> found that it only checks the name of the index. Not what the index >> actually does. This is why I changed that piece of code to be a bit >> smarter. It is desinged for simple constraints from one column to >> another column. Not for multi to multi column indexes and constraints. >> >> I created a Jira issue for it but nobody notices it and there are no >> comments or anything else. So now I try it here :) >> Jira HHH-10934 (https://hibernate.atlassian.net/browse/HHH-10934) >> >> Code fragment I put in SchemaMigratorImpl.java: >> >> private ForeignKeyInformation findMatchingForeignKey(ForeignKey >> foreignKey, TableInformation tableInformation) { >> if (foreignKey.getName() ==null) { >> return null; >> } >> >> /* >> * Find existing keys based on referencing column and >> referencedTable >> */ >> String referencingColumn = foreignKey.getColumn(0).getName(); >> String referencedTableName = foreignKey.getReferencedTable( >> ).getName(); >> Iterable<ForeignKeyInformation> existingForeignKeys = >> tableInformation.getForeignKeys(); >> for (ForeignKeyInformation existingKey : existingForeignKeys) { >> Iterable<ColumnReferenceMapping> columnReferenceMappings >> = existingKey.getColumnReferenceMappings(); >> for (ColumnReferenceMapping mapping : >> columnReferenceMappings) { >> String existingReferencingColumn = >> mapping.getReferencingColumnMetadata().getColumnIdentifier().getText(); >> String existingReferencedTableName = >> mapping.getReferencedColumnMetadata().getContainingTableInfo >> rmation().getName().getTableName().getCanonicalName(); >> if >> (referencingColumn.equals(existingReferencingColumn) >> && referencedTableName.equals(existingReferencedTableName)) { >> return existingKey; >> } >> } >> } >> >> // If not yet found check based on key name return >> tableInformation.getForeignKey(Identifier.toIdentifier( >> foreignKey.getName())); >> } >> >> Or if you prever the Java 8 way: >> >> private ForeignKeyInformation findMatchingForeignKey(ForeignKey >> foreignKey, TableInformation tableInformation) { >> log.debug("findMatchingForeignKey"); >> if (foreignKey.getName() ==null)return null; >> >> /* >> * Find existing keys based on referencing column and >> referencedTable >> */ >> String referencingColumn = foreignKey.getColumn(0).getName(); >> String referencedTableName = foreignKey.getReferencedTable( >> ).getName(); >> Predicate<ColumnReferenceMapping> mappingPredicate = m -> >> referencingColumn.equals(m.getReferencingColumnMetadata(). >> getColumnIdentifier().getText()) >> && referencedTableName.equals(m.g >> etReferencedColumnMetadata().getContainingTableInformation() >> .getName().getTableName().getCanonicalName()); >> for (ForeignKeyInformation existingKey : >> tableInformation.getForeignKeys()) { >> boolean found = StreamSupport.stream(existingK >> ey.getColumnReferenceMappings().spliterator(),false). >> anyMatch(mappingPredicate); >> if (found)return existingKey; >> } >> >> // If not yet found check based on key name return >> tableInformation.getForeignKey(Identifier.toIdentifier( >> foreignKey.getName())); >> } >> >> The calling method does not use the returned value. It only checks if >> the returned value is null or not. So this could also be cleaned by >> changing the method to return a boolean and then remove the for loop in >> java-8 and use flatmap. But first let us agree on the validity of the >> idea to change this piece of code. >> >> I hope anybody would like to have a look at it and if there is any >> change that the idea (not this actual very quick/dirty implementation) >> goes into the system I'll clean it up and do some actual tests for more >> complex database structures. I did not even check the junit tests yet. >> At the moment it is good enough for me but I think it could be something >> more people would benefit from. >> >> Thanks, >> Milo van der Zee >> >> >> _______________________________________________ >> hibernate-dev mailing list >> hibernate-dev@lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/hibernate-dev >> > > > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
