[ https://issues.jboss.org/browse/TEIID-2152?page=com.atlassian.jira.plugin... ] Steven Hawkins commented on TEIID-2152: --------------------------------------- Not quite yet. That will of course be posted before this is resolved. The short form is this merge is just a modified insert statement, just like h2. Also like h2 when a key clause is not specified we assume that the primary key (or first unique key) of the table is being used to ensure uniqueness. That support can be expanded, but the pk will likely be the most common case. The implementation simply performs an existence check for each row being merged and perform an update if the row exists. That of course could be optimized a little more in this simple case. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira