Derby - constraints
问题 In the Derby server, how can you use the information in the system tables of the schema to create a select statement in order to retrieve the constraint names for each table? 回答1: The relevant manual is the Derby Reference Manual. There are many versions available: 10.13 was current in April 2017, but it was 10.3 in May 2009. Original answer SELECT c.constraintname, t.tablename FROM sysconstraints c, systables t WHERE c.tableid = t.tableid; Since sufficiently recent versions of Derby require