sys.check_constraints

每个用作 CHECK 约束（sys.objects.type = C）的对象都在表中占一行。

SELECT  name

FROM    sys.check_constraints



-- equal to

SELECT  o.name

FROM    sys.sysobjects o

        JOIN sys.sysconstraints s ON o.parent_obj = s.id

WHERE   o.xtype = 'C'

GROUP BY o.name

sys.check_constraints (Transact-SQL)