Hello all,
We are using event triggers to capture DDL for subsequent replay on a logical replica.
The intention is to write the DDL statement to a table, inside the same transaction that executes the DDL, and have a
separateprocess on the replica notice changes in this table and execute whatever it finds.
We have declared a trigger on the ddl_command_end event for this purpose. We can get the SQL from running
current_query()inside the trigger; oddly, the pg_event_trigger_ddl_commands() function does have an attribute called
"command",typed as "pg_ddl_command", but there are no SQL functions that can operate on this type, including turning it
intoa string.
This process works for a simple case of e.g. "CREATE TABLE t()".
However, in other cases --- e.g. "DO $$ BEGIN CREATE TABLE t(); CREATE TABLE s(); END; $$;" --- the trigger will fire
foreach CREATE TABLE but the current_query() will evaluate to the entire DO block.
This makes it difficult to capture just the actual statement that is being executed. I am looking for a way to get the
precisestatement that is being executed from within the ddl_command_event trigger function. Does anyone know if this
ispossible?
Thanks,
-Joe
