Question

Suppose I have an AFTER ALTER trigger on my Oracle database and I rename some database object (ALTER ... RENAME TO ...). Within the trigger, how do I determine the new name of the database object? It seems that the ORA_DICT_OBJ_OWNER, ORA_DICT_OBJ_NAME and ORA_DICT_OBJ_TYPE functions all return the old values of the database object.

For example:

CREATE OR REPLACE TRIGGER ADAM_BEFORE_AFTER BEFORE ALTER ON DATABASE
BEGIN
  DBMS_OUTPUT.put_line('Before alter: ' || ora_dict_obj_owner || '.' || ora_dict_obj_name || ' (' || ora_dict_obj_type || ')');
END;

CREATE OR REPLACE TRIGGER ADAM_AFTER_ALTER AFTER ALTER ON DATABASE
BEGIN
  DBMS_OUTPUT.put_line('After alter: ' || ora_dict_obj_owner || '.' || ora_dict_obj_name || ' (' || ora_dict_obj_type || ')');
END;

Suppose I rename a table:

ALTER TABLE USELESS_TABLE9 RENAME TO USELESS_TABLE10

The database outputs this:

Before alter: DEVELOPER.USELESS_TABLE9 (TABLE)
After alter: DEVELOPER.USELESS_TABLE9 (TABLE)

Update: Unfortunately, the output I presented above was incorrect. The output was actually being generated by a BEFORE DDL trigger and an AFTER DDL trigger I had created earlier, not by the BEFORE RENAME and AFTER RENAME triggers. I will continue to investigate why the BEFORE RENAME and AFTER RENAME triggers are not firing…

Update: It appears that the BEFORE RENAME and AFTER RENAME triggers refuse to fire, but the BEFORE ALTER and AFTER ALTER triggers do. I have updated the question accordingly.

Answer 1

ALTER RENAME won’t fire the trigger, RENAME x TO y will.

As for your question about names before and after, I think you will have to parse the DDL to retrieve them, like that:

CREATE OR REPLACE TRIGGER MK_BEFORE_RENAME BEFORE RENAME ON SCHEMA 
DECLARE 
  sql_text ora_name_list_t;
  v_stmt VARCHAR2(2000);
  n PLS_INTEGER; 
BEGIN  
  n := ora_sql_txt(sql_text);
  FOR i IN 1..n LOOP
   v_stmt := v_stmt || sql_text(i);
  END LOOP;

  Dbms_Output.Put_Line( 'Before: ' || regexp_replace( v_stmt, 'rename[[:space:]]+([a-z0-9_]+)[[:space:]]+to.*', '\1', 1, 1, 'i' ) );
  Dbms_Output.Put_Line( 'After: ' || regexp_replace( v_stmt, 'rename[[:space:]]+.*[[:space:]]+to[[:space:]]+([a-z0-9_]+)', '\1', 1, 1, 'i' ) );
END;

The regular expressions could surely be written more clearly, but it works:

RENAME 
mktestx
TO                 mktesty;

Before: mktestx
After: mktesty

UPDATE To accommodate your changed question:

CREATE OR REPLACE TRIGGER MK_AFTER_ALTER AFTER ALTER ON SCHEMA 
DECLARE 
  sql_text ora_name_list_t;
  v_stmt VARCHAR2(2000);
  n PLS_INTEGER; 
BEGIN  
  n := ora_sql_txt(sql_text);
  FOR i IN 1..n LOOP
   v_stmt := v_stmt || sql_text(i);
  END LOOP;

  Dbms_Output.Put_Line( 'Before: ' || regexp_replace( v_stmt, 'alter[[:space:]]+table[[:space:]]+([a-z0-9_]+)[[:space:]]+rename[[:space:]]+to.*', '\1', 1, 1, 'i' ) );
  Dbms_Output.Put_Line( 'After: ' || regexp_replace( v_stmt, 'alter[[:space:]]+table[[:space:]]+.*to[[:space:]]+([a-z0-9_]+)', '\1', 1, 1, 'i' ) );
END;