Alter database design with JPA -

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i working on database jpa , curios altering database design. lets have table , want add/remove column in table.

i have tried re-deploying technique did not work me. using jpa 2.0

so, want know there standard way alter database tables or manually add/remove table's design? possible change primary key of table ?

any highly appreciated.

thanks :)

for non-production dbs can use persistence.xml properties either create, drop-create or update existing db schema (example hibernate):

<persistence ...>   <persistence-unit ...>     <property name="hibernate.hbm2ddl.auto" value="create-drop" />

for eclipselink, property name different , available options:

<property name="eclipselink.ddl-generation" value="create-tables"/> <property name="eclipselink.ddl-generation.output-mode" value="database"/>

for production dbs stick manual changes have careful details , timing.


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