Both servers are Oracle 8.1.7.4 EE 64 bit on AIX 4.3.x, should be same patch and maintenance level. Anyone seen this type of behavior before? I connected to each database directly on the server using SQL*Plus. SERVER1>/ select g1tax, count(*) from crpdta.f045143 where g1an8 in ('V','R','D') group by g1tax having count(*) > 1 * ERROR at line 1: ORA-01722: invalid number SERVER2> select g1tax, count(*) from proddta.f045143 where g1an8 in ('V','R','D') group by g1tax having count(*) > 1; select g1tax, count(*) from proddta.f045143 where g1an8 in ('V','R','D') group by g1tax having count(*) > 1 * ERROR at line 1: ORA-03113: end-of-file on communication channel