×

Loading...
Ad by
  • 推荐 OXIO 加拿大高速网络，最低月费仅$40. 使用推荐码 RCR37MB 可获得一个月的免费服务
Ad by
  • 推荐 OXIO 加拿大高速网络，最低月费仅$40. 使用推荐码 RCR37MB 可获得一个月的免费服务

@Calgary

I have no environmet of MySQL however here is my test in Oracle.

cyt(糖炒栗子)
本文发表在 rolia.net 枫下论坛SQL> select * from dept;

DEPTNO DNAME LOC F
--------- -------------- ------------- -
10 ACCOUNTING NEW YORK N
20 RESEARCH DALLAS Y
30 SALES CHICAGO Y
40 OPERATIONS BOSTON Y

SQL> select * from emp;

EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
--------- ---------- --------- --------- --------- --------- --------- ---------
7369 SMITH CLERK 7902 17-DEC-80 800 80 20
7499 ALLEN SALESMAN 7698 20-FEB-81 1600 160 30
7521 WARD SALESMAN 7698 22-FEB-81 1250 125 30
7566 JONES MANAGER 7839 02-APR-81 2975 297.5 20
7654 MARTIN SALESMAN 7698 28-SEP-81 1250 125 30
7698 BLAKE MANAGER 7839 01-MAY-81 2850 285 30
7782 CLARK MANAGER 7839 09-JUN-81 2450 245 10
7788 SCOTT ANALYST 7566 19-APR-87 3000 300 20
7839 KING PRESIDENT 17-NOV-81 5000 500 10
7844 TURNER SALESMAN 7698 08-SEP-81 1500 150 30
7876 ADAMS CLERK 7788 23-MAY-87 1100 110 20
7900 JAMES CLERK 7698 03-DEC-81 1050 105 30
7902 FORD ANALYST 7566 03-DEC-81 3000 300 20
7934 MILLER CLERK 7782 23-JAN-82 1300 130 10
100 TTT

15 rows selected.

SQL> create view emp_dept as select emp.ename,dept.dname from emp,dept where emp.deptno=dept.deptno;

View created.

SQL> select * from emp_dept;

ENAME DNAME
---------- --------------
SMITH RESEARCH
ALLEN SALES
WARD SALES
JONES RESEARCH
MARTIN SALES
BLAKE SALES
CLARK ACCOUNTING
SCOTT RESEARCH
KING ACCOUNTING
TURNER SALES
ADAMS RESEARCH
JAMES SALES
FORD RESEARCH
MILLER ACCOUNTING

14 rows selected.

SQL> update emp_dept set dname='sales' where dname='SALES';
update emp_dept set dname='sales' where dname='SALES'
*
ERROR at line 1:
ORA-01779: cannot modify a column which maps to a non key-preserved table更多精彩文章及讨论，请光临枫下论坛 rolia.net
(#418140@0)
Last Updated: 2002-3-25
This post has been archived. It cannot be replied.
Report

Replies, comments and Discussions:

  • 工作学习 / IT技术讨论 / 求助：在Access里通过MyODBC链接MySQL数据库中的表T1、T2并建立关系后，创建窗体F以便输入数据，却发现不能更改或增删窗体F中的数据。而单独以表T1或表T2为基础的窗体F1、F2中是可以的，这是怎么回事？ -agincourt(百灵鸟); 2002-3-24 {67} (#417059@0)
    软件版本为：

    MySQL 3.23
    MyODBC 2.50/3.51
    Access 2002
    • try build the same two tables within Access, and see if you can modify the data or not? -mcdonald(麦当劳); 2002-3-24 (#417099@0)
      • 什么叫“build the same two tables within Access”？建立链接后，在Access里是可以更改表中的数据的，仅包含其中一个表中的ields的窗体也可以；只是窗体中如包含两个表的fields就不能更改了。 -agincourt(百灵鸟); 2002-3-24 (#417339@0)
        • 我想这里的窗体相当于数据库中的视图（view）。有一些视图是不可更改的。看你的窗体是一个什么样的查询。 -cyt(糖炒栗子); 2002-3-24 (#417357@0)
          • 窗体是基于两张有关联的表，而不是查询。窗体及其中的控件也都没有禁止写功能。关键是基于任一张表的窗体是可以写的，但加入另一张表的fields就不行了。 -agincourt(百灵鸟); 2002-3-25 (#417906@0)
            • I have no environmet of MySQL however here is my test in Oracle. -cyt(糖炒栗子); 2002-3-25 {2420} (#418140@0)
              本文发表在 rolia.net 枫下论坛SQL> select * from dept;

              DEPTNO DNAME LOC F
              --------- -------------- ------------- -
              10 ACCOUNTING NEW YORK N
              20 RESEARCH DALLAS Y
              30 SALES CHICAGO Y
              40 OPERATIONS BOSTON Y

              SQL> select * from emp;

              EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
              --------- ---------- --------- --------- --------- --------- --------- ---------
              7369 SMITH CLERK 7902 17-DEC-80 800 80 20
              7499 ALLEN SALESMAN 7698 20-FEB-81 1600 160 30
              7521 WARD SALESMAN 7698 22-FEB-81 1250 125 30
              7566 JONES MANAGER 7839 02-APR-81 2975 297.5 20
              7654 MARTIN SALESMAN 7698 28-SEP-81 1250 125 30
              7698 BLAKE MANAGER 7839 01-MAY-81 2850 285 30
              7782 CLARK MANAGER 7839 09-JUN-81 2450 245 10
              7788 SCOTT ANALYST 7566 19-APR-87 3000 300 20
              7839 KING PRESIDENT 17-NOV-81 5000 500 10
              7844 TURNER SALESMAN 7698 08-SEP-81 1500 150 30
              7876 ADAMS CLERK 7788 23-MAY-87 1100 110 20
              7900 JAMES CLERK 7698 03-DEC-81 1050 105 30
              7902 FORD ANALYST 7566 03-DEC-81 3000 300 20
              7934 MILLER CLERK 7782 23-JAN-82 1300 130 10
              100 TTT

              15 rows selected.

              SQL> create view emp_dept as select emp.ename,dept.dname from emp,dept where emp.deptno=dept.deptno;

              View created.

              SQL> select * from emp_dept;

              ENAME DNAME
              ---------- --------------
              SMITH RESEARCH
              ALLEN SALES
              WARD SALES
              JONES RESEARCH
              MARTIN SALES
              BLAKE SALES
              CLARK ACCOUNTING
              SCOTT RESEARCH
              KING ACCOUNTING
              TURNER SALES
              ADAMS RESEARCH
              JAMES SALES
              FORD RESEARCH
              MILLER ACCOUNTING

              14 rows selected.

              SQL> update emp_dept set dname='sales' where dname='SALES';
              update emp_dept set dname='sales' where dname='SALES'
              *
              ERROR at line 1:
              ORA-01779: cannot modify a column which maps to a non key-preserved table更多精彩文章及讨论，请光临枫下论坛 rolia.net
            • 你有没有建立“正确”的关联呢? 而且关联字段必须有索引。还有： check你的ODBCdirect 代码。 -elife(候鸟); 2002-3-25 (#419172@0)
        • 我只是在猜想,因为你用ODBC访问MySQL,Access没办法帮你自动生成相应的update语句并保持表的相关一致.你可能要写些SQL代码才行了. -mcdonald(麦当劳); 2002-3-25 (#418153@0)

More Topics

  • 现在社区游泳池招救生员巡逻，过一会还要不停的点人头，这工作是否很快就被AI代替了，装一个摄像头后面是AI处理系统，这样只招一个等着救人就行了，人头沉下水一定时间立马强光照射，还可以分析水下人的状况来判断是否溺水等
  • 新冠疫苗引发心肌炎? 最新研究这样看
  • 这道几何题有解吗?
  • SAM 2 Demo
  • 如何在 AWS EC2 实例上构建 WordPress 应用程序?
    • 枫下论坛主坛 /  工作学习 /  IT技术讨论