文档解释
ORA-30731: scope constraint not allowed on nested table column when the nested table is being created
Cause: An attempt was made to define a scope constraint on a nested table column when the nested table is being created.
Action: Do not specify a scope constraint on a nested table column when creating it. Instead, specify it using the ALTER TABLE statement.
。
这是一个Oracle错误，它指出在创建嵌套表时不允许在嵌套表列上指定范围约束。
官方解释
Oracle Error Message ORA-30731: “scope constraint not allowed on nested table column when the nested table is being created”
Cause: The CREATE TABLE statement specified a SCOPE clause in the definition of a nested table.
Action: Do not specify a SCOPE clause in the definition of a nested table.
常见案例
这个错误通常发生在尝试创建一个嵌套表时，而其定义不正确，尤其是在定义器表中指定SCOPE约束时。以下是一个嵌套表定义出错的示例：
CREATE TABLE nested_table (
col1 NUMBER,
col2 NUMBER,
col3 SCOPE constraint
col4 NESTED TABLE …
);
一般处理方法及步骤
对于上述情况，要解决这个错误，您需要修改嵌套表的定义，并去除SCOPE约束条款。也就是说，正确的表定义看起来应该像这样：
CREATE TABLE nested_table (
col1 NUMBER,
col2 NUMBER,
col4 NESTED TABLE …
);
