I encountered an infinite loop when submitting DDL from a remote Avatica driver (using sqlline) against a LocalService wrapping CalciteMetaImpl.
I was able to debug the issue and verified a fix.
The problem was that in CalciteMetaImpl.prepareAndExecute, the updateCount is not being passed to the MetaResultSet constructor. Instead, the updateCount is always set to -1. This incorrectly instructs the remote Avatica driver to fetch results when there aren't any, which causes it to loop.
By fixing the CalciteMetaImpl.prepareAndExecute method to set the updateCount in MetaResultSet, I was able to fix the infinite loop.