How to resolve EXP-00056: ORACLE error 19206 encountered during an export

Posted by David Yahalom under Oracle

Sometimes you might receive the following error during an export of an entire schema in Oracle9i/10g:

EXP-00056: ORACLE error 19206 encountered
ORA-19206: Invalid value for query or REF CURSOR parameter
ORA-06512: at "SYS.DBMS_XMLGEN", line 83
ORA-06512: at "SYS.DBMS_METADATA", line 353
ORA-06512: at "SYS.DBMS_METADATA", line 418
ORA-06512: at "SYS.DBMS_METADATA", line 457
ORA-06512: at "SYS.DBMS_METADATA", line 1181
ORA-06512: at "SYS.DBMS_METADATA", line 1162
ORA-06512: at line 1
EXP-00056: ORACLE error 19206 encountered
ORA-19206: Invalid value for query or REF CURSOR parameter
ORA-06512: at "SYS.DBMS_XMLGEN", line 83
ORA-06512: at "SYS.DBMS_METADATA", line 353
ORA-06512: at "SYS.DBMS_METADATA", line 418
ORA-06512: at "SYS.DBMS_METADATA", line 457
ORA-06512: at "SYS.DBMS_METADATA", line 1181
ORA-06512: at "SYS.DBMS_METADATA", line 1162
ORA-06512: at line 1
EXP-00000: Export terminated unsuccessfully

While an export of a single table might work, exporting an entire user (”schema“) will fail with the above error.

This problem is caused when the metadata tables needed to perform an export are missing or invalid and can sometimes occur if you have dropped or modified the XMLDB schema.

It is quite easily resolved, simply run the following script when connected as sysdba:

$ORACLE_HOME/rdbms/admin/catmeta.sql