Search notes:

ORA-01400: cannot insert NULL into …

create table ora_01400 (
   foo number not null,
   bar number not null,
   baz number not null
);
The following insert statement throws: ORA-01400: cannot insert NULL into ("RENE"."ORA_01400"."BAR"):
insert into ora_01400 values (1, null, 3);

See also

not null constraints.
Other Oracle error messages (such as ORA-01407: cannot update … to NULL)

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