using
< property name="hbm2ddl.auto"> create< / property >
only creates the tables, and whenever a schema does not exist, hibernate fails to create the table because the schema does not exist.
Hibernate will not create the schema for you, but maybe you can tell your DBMS to run some script before hibernate starts to create the schema objects. I found something here and I think you can use it as a start point.
Related
I have a database and I generated all bean and hbm.xml files with hibernate tool.
I noticed this tool not generated automatically the cascade property... I read it can be done using reveng.xml.
There are ways to auto-generate revenge.xml, or set a cascade property 1 time for all tables?
There are multiple options for the auto property:
create - It creates new tables corresponding mapping or annotation. It drops existing tables and data.
update - It keeps existing data and tables. It updates the schema.
here we have to take care contracts.
create-drop - It is same like create but once session gets closed it
drops everything.
validate - it validates or matches schema with map or annotation.
It's valid for a Production environment.
Propery hbm2ddl.auto = update in configuration xml.
If you want to delete cascade you should add to your collection in XML the following:
cascade="delete-orphan"
cascade="save-update, delete"
hi I have an entity with this annotation
#Entity
#Table(name = "REPORT_WORK")
But for some reason hibernate keep saying Missing Table: REPORT_REPORT_WORK
I know that is the problem because of when I change the name to "REPORT_WORKX"
It will say Missing Table: REPORT_REPORT_WORKX
Has any encountered this issue before?
Update: when I change the name to JJJJ
It will say Missing Table: REPORT_JJJJ
so for some reason there it is auto appending REPORT_
Configuration:
hibernate.hbm2ddl.auto=validate
I suspect that the problem is your Hibernate configurations. Specifically, if you don't have an appropriate setting for hibernate.hbm2ddl.auto, Hibernate won't automatically update the database schema when you change your model.
(And if you don't want the updates to happen automatically, then you need to figure out what schema changes are needed, code them as SQL DDL, and run them manually.)
Can you post your persistence.xml (or equivalent)?
It sounds like you are implementing org.hibernate.cfg.NamingStrategy, get rid of this configuration.
Some additional info:
JPA (Hibernate) and custom table prefixes
I have an issue testing a Hibernate application which queries multiple catalogs/schemas.
The production database is Sybase and in addition to entities mapped to the default catalog/schema there are two entities mapped as below. There are therefore three catalogs in total.
#Table(catalog = "corp_ref_db", schema = "dbo", name = "WORKFORCE_V2")
public class EmployeeRecord implements Serializable {
}
#Table(catalog = "reference", schema = "dbo", name="cntry")
public class Country implements Serializable {
}
This all works in the application without any issues. However when unit testing my usual strategy is to use HSQL with hibernate's ddl flag set to auto and have dbunit populate the tables.
This all works fine when the tables are all in the same schema.
However, since adding these additional tables, testing is broken as the DDL will not run as HSQL only supports one catalog.
create table corp_ref_db.dbo.WORKFORCE_V2
user lacks privilege or object not found: CORP_REF_DB
If there were only two catalogs then I think it would maybe be possible to get round this by changing the default catalog and schema in the HSQL database to that one explicitly defined:
Is there any other in-memory database for which this might work or is there any strategy for getting the tests to run in HSQL.
I had thought of providing an orm.xml file which specified the default catalog and schema (overiding any annotations and having all the defined tables created in the default catalog/schema) however these overrides do not seem to be observed when the DDL is executed i.e. I get the same error as above.
Essentially, then I would like to run my existing tests and either somehow have the tables created as they are defined in the mappings or somehow override the catalog/schema definitions at the entity level.
I cannot think of any way to achieve either outcome. Any ideas?
I believe H2 supports catalogs. I haven't used them in it myself, but there's a CATALOGS table in the Information Schema.
I managed to achieve something like this in H2 via IGNORE_CATALOGS property and version 1.4.200
However, the url example from their docs did not seem to work for me, so I added a statement in my schema.xml:
SET IGNORE_CATALOGS = true;
I have witten the POJO class, *.cfg.xml file, *.hbm.xml file and hibernate code to retrieve data.
But I didn't created any table. Is there any tag available in hibernate which will create table by using configuration files.
How to implement reverse engineering in hibernate ?
Thanks !
You can actually set a configuration property and instruct hibernate to create the database schema for you.
hibernate.hbm2ddl.auto = create-drop | update
See this link Asking hibernate to generate schema for you
Looks like jpa is something which makes me ask a lot of questions.
Having added this
<property name="toplink.ddl-generation" value="create-tables"/>
my JPA application always creates tables when running, which results in exceptions in case the tables already exist. I would like JPA to check if the tables already exist and if not create them, however I could not find a value for the property above which does this.
So if I just turn it off, is there a way to tell JPA manually at some point to create all the tables?
Update here's the exception I get
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'tags' already exists
Error Code: 1050
Call: CREATE TABLE tags (ID BIGINT AUTO_INCREMENT NOT NULL, NAME VARCHAR(255), OCCURRENCE INTEGER, PRIMARY KEY (ID))
MySQLSyntaxErrorException?! Now that's wrong for sure
According to http://www.oracle.com/technology/products/ias/toplink/JPA/essentials/toplink-jpa-extensions.html#Java2DBSchemaGen toplink does not have an option to update exiting tables, I'm not sure if I would trust it to do the right thing anyway.
You could configure toplink to generate a sql script that you then would have to execute manually to create all tables. The filenames and location can be configured like this:
<property name="toplink.ddl-generation" value="create-tables"/>
<property name="toplink.ddl-generation.output-mode" value="sql-script"/>
<property name="toplink.create-ddl-jdbc-file-name" value="createDDL.sql"/>
<property name="toplink.drop-ddl-jdbc-file-name" value="dropDDL.sql"/>
<property name="toplink.application-location" value="/tmp"/>
I would like [my] JPA [provider] to check if the tables already exist and if not create them, however I could not find a value for the property above which does this.
Weird, according to the TopLink Essentials documentation about the toplink.ddl-generation extension, create-table should leave existing table unchanged:
TopLink JPA Extensions for Schema Generation
Specify what Data Descriptor Language
(DDL) generation action you want for
your JPA entities. To specify the DDL
generation target, see
toplink.ddl-generation.output-mode.
Valid values: oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider
none - do not generate DDL; no
schema is generated.
create-tables - create DDL for
non-existent tables; leave existing
tables unchanged (see also
toplink.create-ddl-jdbc-file-name).
drop-and-create-tables - create DDL for all tables; drop all existing
tables (see also
toplink.create-ddl-jdbc-file-name
and
toplink.drop-ddl-jdbc-file-name).
If you are using persistence outside
the EJB container and would like to
create the DDL files without creating
tables, additionally define a Java
system property INTERACT_WITH_DB and
set its value to false.
Liquibase (http://www.liquibase.org) is good at this. It takes some time to get fully used to it, but I think it's worth the effort.
The Liquibase-way is independent of which JPA persistence provider you use. Actually, it's even database agnostic.