Question

不确定我错过了什么来获得此错误？

  Error starting at line : 95 in command -
    ALTER TABLE Official_Language ADD CONSTRAINT Language_Official_Language_fk
    FOREIGN KEY (language_code)
    REFERENCES Language (language_code)
    ON DELETE NO ACTION
    ON UPDATE NO ACTION
    NOT DEFERRABLE
    Error report -
    SQL Error: ORA-00905: missing keyword
    00905. 00000 -  "missing keyword"
    *Cause:    
    *Action:

感谢任何帮助:-)谢谢

Answer 1

ALTER TABLE Official_Language ADD CONSTRAINT Language_Official_Language_fk
FOREIGN KEY (language_code)
REFERENCES Language (language_code)
NOT DEFERRABLE;

可能的选择是ON DELETE [CASCADE | SET NULL] 默认情况下（如果省略ON DELETE），它与您编写的相同。

NOT DEFERRABLE是默认值（你也可以省略它）

Answer 2

这个应该有效：

ALTER TABLE Official_Language ADD CONSTRAINT Language_Official_Language_fk
    FOREIGN KEY (language_code)
    REFERENCES Language (language_code)
    NOT DEFERRABLE;

默认为＆＃34;无操作＆＃34;，Oracle对删除/更新没有任何影响。

可能的关键字为ON DELETE CASCADE或ON DELETE SET NULL

Answer 3

与MySql不同，Oracle不支持ON DELETE NO ACTION - 选项为：

（无）（即强制执行参照完整性）
ON DELETE CASCADE（即级联删除）
ON DELETE SET NULL（如果列可为空，则将键更新为null）

Reference

SqlFiddle here

SQL错误：ORA-00905：缺少关键字，ON DELETE NO ACTION外键

3 个答案: