假设我们有一个具有表数量的数据库“业务”。如果您只想显示外键约束,请使用以下查询-
mysql> select * −> from information_schema.referential_constraints −> where constraint_schema = 'business';
以下是仅显示外键约束的输出-
+--------------------+-------------------+--------------------------+---------------------------+--------------------------+------------------------+--------------+-------------+-------------+-------------------+-----------------------+ | CONSTRAINT_CATALOG | CONSTRAINT_SCHEMA | CONSTRAINT_NAME | UNIQUE_CONSTRAINT_CATALOG | UNIQUE_CONSTRAINT_SCHEMA | UNIQUE_CONSTRAINT_NAME | MATCH_OPTION | UPDATE_RULE | DELETE_RULE | TABLE_NAME | REFERENCED_TABLE_NAME | +--------------------+-------------------+--------------------------+---------------------------+--------------------------+------------------------+--------------+-------------+-------------+-------------------+-----------------------+ | def | business | ConstChild | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | childdemo | parentdemo | | def | business | ConstFK | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | tblf | tblp | | def | business | constFKPK | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | foreigntable | primarytable1 | | def | business | FKConst | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | foreigntabledemo | primarytabledemo | | def | business | primarytable1demo_ibfk_1 | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | primarytable1demo| foreigntable1 | | def | business | StudCollegeConst | def | business | PRIMARY | NONE | NO ACTION | NO ACTION | studentenrollment| college | +--------------------+-------------------+--------------------------+---------------------------+--------------------------+------------------------+--------------+-------------+-------------+-------------------+-----------------------+ 6 rows in set (0.07 sec)