I'd like an API to inspect and rewrite a user query/command before it reaches the Teiid planner. The use case is to rewrite the query/command to implement view-like capabilities. For example:
SELECT a,b,c FROM table1 AS t WHERE t.a='xyz' would be rewritten as:
SELECT a,b,c FROM (SELECT a,b,c FROM table2 UNION SELECT a,b,c FROM table3) AS t

I imagine this API would be similar to the translator API: it would receive a data structure representing the query/command and use a visitor to rewrite the query. As a convenience, it would be nice to have something similar to the SQLConversionVisitor.