If informational check constraints exist on the primary key column, you should explicitly specify informational check constraints on their corresponding foreign key columns. For example.
如果在主键列上存在信息检查约束,那么应该在它们相应的外键列上指定信息检查约束。
You can also use the system catalog views to retrieve information about NOT NULL, unique, primary key, foreign key, and table check constraints. For example.
也可以使用系统编目视图来检索关于NOT NULL、惟一、主键、外键和表检查约束的信息。
Syscat.tabconst Contains a row for each unique (u), primary key (p), foreign key (f), or table check (k) constraint db2 select constname, tabname, type from syscat.tabconst.
tabconst为每个唯一性(U)、主键(p)、外键(f)或者表检查(K)约束保持一个行db2 select constname, tabname, type from syscat . tabconst。
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