In our Connecting JIRA to Oracle documentation, the following is stated:

Note, the <database-type/> element must specify your type of database, e.g. oracle11g. If you forget to do this and you start JIRA, your database tables may be created incorrectly.

Sample dbconfig.xml file

For more information about the child elements of <jdbc-datasource/> beginning with pool in the dbconfig.xml file above, see Tuning Database Connections.

<?xml version="1.0" encoding="UTF-8"?>
 
<jira-database-config>
  <name>defaultDS</name>
  <delegator-name>default</delegator-name>
  <database-type>oracle11g</database-type>
  <jdbc-datasource>
    <url>jdbc:oracle:thin:@dbserver:1521:ORCL</url>
    <driver-class>oracle.jdbc.OracleDriver</driver-class>
    <username>jiradbuser</username>
    <password>password</password>
    <pool-min-size>20</pool-min-size>
    <pool-max-size>20</pool-max-size>
    <pool-max-wait>30000</pool-max-wait>
    <pool-max-idle>20</pool-max-idle>
    <pool-remove-abandoned>true</pool-remove-abandoned>
    <pool-remove-abandoned-timeout>300</pool-remove-abandoned-timeout>
 
    <validation-query>select 1 from dual</validation-query>
    <min-evictable-idle-time-millis>60000</min-evictable-idle-time-millis>
    <time-between-eviction-runs-millis>300000</time-between-eviction-runs-millis>
   
    <pool-test-while-idle>true</pool-test-while-idle>
  </jdbc-datasource>
</jira-database-config>

However, JIRA does not have a oracle11g definition, and configuring JIRA to use that cause JIRA to fail to start correctly. Therefore, we need to fix this information in our documentation to avoid further problems for our customers.