ORA-06512: at "SYS.DBMS_XMLGEN", (ORA-00942: table or view does not exist)

Question

Hey Guys, it's Xev.
I decide to  use SQL and XML and it works in one scenario, but in another scenario, it doesn't.
Here is the Code, I am passing in two variables, First, I pass in the table_name and then i pass in the schema.
If I am doing this with the "user" connected and it's looking in it's own schema, it's find the results, like so, but if i try to execute this code while not
connected to the same user i am searching on i get this error.
ORA-19202: Error occurred in XML processing
ORA-00942: table or view does not exist
ORA-06512: at "SYS.DBMS_XMLGEN", line 288
ORA-06512: at line 1
19202. 00000 -  "Error occurred in XML processing%s"
*Cause:    An error occurred when processing the XML function
*Action:   Check the given error message and fix the appropriate problem
This code works only of you are connected to the user that you are searching on.
But if you search for another user tables, it's blows up and gives the XML error above...
SET SERVEROUTPUT ON
exec DBMS_OUTPUT.ENABLE(1000000);
VAR search_string VARCHAR2(28)
EXEC :search_string := '^[0-9]{3}-[0-9]{2}-[0-9]{4}$'
COLUMN "Searchword"     FORMAT A28
COLUMN "Table"     FORMAT A9
COLUMN "Column/Value" FORMAT A50
SELECT DISTINCT SUBSTR (:search_string, 1, 28) "Searchword",
                 SUBSTR (table_name, 1, 14) "Table",
                 SUBSTR (t.column_value.getstringval (), 1, 50) "Column/Value"
    FROM   dba_tab_cols,
    --where owner = ('&SCHEMA_NAME')
            TABLE
              (XMLSEQUENCE
             (DBMS_XMLGEN.GETXMLTYPE
                ( 'SELECT ' || column_name ||
                 ' FROM ' || table_name ||
               ' WHERE REGEXP_LIKE
                     (' || column_name || ','''
                    || :search_string || ''')'
              ).extract ('ROWSET/ROW/*'))) t
  --WHERE  table_name IN ('FIND_TEST')
  WHERE table_name = upper('&TABLE_NAME')
  AND OWNER = upper('&SCHEMA_NAME')
  ORDER  BY "Table"
Can someone please explain how (DBMS_XMLGEN) works, and why it's throwing that error??
thanks,
Xev.

Answer 1

It has nothing to do with DBMS_XMLGEN.GETXMLTYPE. It simply means user executing your SQL has no select privilege on table &SCHEMA_NAME.&TABLE_NAME.
SY.