You used the MySQL JNDI when generating the WAR. You need to create a datasource for the VDB and use that JNDI for the generated WAR.
I did it. I have the datasource in standalone-teiid.xml and started the server with this file. My VDB also includes the source model for MySQL database and the view model with a procedure defined. Actually I can create a procedure directly from the source model (in this way I do not need a virtual model), but as I created REST WAR from the VDB, I got an error from the webservice plugin (runtime.ui) that says syntax error with ";". Hence, I went around in another way.
thanks a lot. I followed the link and made it now. The problem was: I added the data source entry manually in standalone-teiid.xml and gave a connection to MySQL. This is wrong. Now I automatically added this from Teiid designer and found that it shall be a connection to Teiid server.