* Should we prohibit DDL from within event triggers?
Please don't prohibit DDL unless there is a really, really good reason to do so. I have several use cases in mind for event triggers, but they are only useful if I can perform DDL.
For example, I want to create an Elasticsearch FDW and use that to index and search Postgres tables. When a table is created, I am planning to use an event trigger to capture the CREATE event and automatically create a foreign table via the Elasticsearch FDW. In addition, I would add normal triggers to the new table which capture DML and update the foreign table accordingly. In other words, I want to use FDWs and event triggers to automatically sync table DDL and DML to Elasticsearch.
