modified persistence JPA and README to add "database.generation" variable to determine

whether or not JPA should create/alter tables in the schema on application startup
Signed-off-by: Neal Ensor <[email protected]>

Author: nensor

README.md

@@ -50,6 +50,7 @@ database.driver | the JDBC database driver to use
 database.url | the JDBC URL to access
 database.user | the database user (with create/alter schema permission)
 database.password | the user's password
+database.generation | JPA database table command; usually "create-or-extend-tables" or "none"
 serviceapi.host | base URL for validation services
 publishing.host | base URL for submitting final metadata to OSTI (via /submit API)
 datacite.user | (optional) DataCite user account name for registering DOIs

src/main/resources/META-INF/persistence.xml

@@ -20,7 +20,7 @@
       <property name="javax.persistence.jdbc.user" value="${database.user}"/>
       <property name="javax.persistence.jdbc.driver" value="${database.driver}"/>
       <property name="javax.persistence.jdbc.password" value="${database.password}"/>
-      <property name="eclipselink.ddl-generation" value="create-or-extend-tables"/>
+      <property name="eclipselink.ddl-generation" value="${database.generation}"/>
     </properties>
   </persistence-unit>
 </persistence>