In this post, you’ll learn about the SQL error code 666 in InterSystems IRIS database the reason why you are receiving the TSQL message when using the InterSystems IRIS data platform
Error Code :
666
Reason for the Error code 666 in InterSystems IRIS DBMS
Maximum system-generated unique value for a duplicate group exceeded for table ID %d, index ID %d. Dropping and re-creating the index may fix the problem; otherwise use another clustering key.