sp_declt:Error: Oracle Error 1400: ORA-01400: cannot insert NULL into ("owner"."table"."col") (4224585)

Compare errors with following event_log errors:
01/22/07 19:38 Internal error: Error -1 in de_compare_client see sebprod_declt-owner-table-pid-*.log [sp_declt(deq)/pid]
01/22/07 18:17 Error: Oracle Error 1400: ORA-01400: cannot insert NULL into
("owner"."table"."col")

This error is thrown if an attempt is made to insert a null into a column that has not null constraint.

Null value is being attempted to be inserted into column with "not null" constraint:
Example:
SQL> insert into nn values(null);
insert into nn values(null) * ERROR at line 1: ORA-01400: cannot insert NULL into ("DEV01"."NN"."D")

RESOLUTION:

Check deferrable primary key constraints: when the constraint is set immediate causing the error