automatically-generated constraint names avoid duplicates in the
same schema, but users can specify such duplicate names.
</para>
+
+ <para>
+ This problem can appear when querying information schema views like
+ <literal>referential_constraints</>, <literal>check_constraints</>,
+ <literal>domain_constraints</>, and
+ <literal>check_constraint_routine_usage</>. Some other views have
+ similar issues but contain the table name to help distinguish
+ duplicate rows, e.g. <literal>table_constraints</>,
+ <literal>constraint_table_usage</>, <literal>constraint_column_usage</>.
+ </para>
</note>