已选择14行。
SQL> host cls
SQL> create synonym remoteemp for emp@l2;
同义词已创建。
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SQL> select ename,dname 2 from dept, remoteemp 3 where remoteemp.deptno=dept.deptno; ENAME DNAME ---------------------------------------- -------------- SMITH RESEARCH ALLEN SALES WARD SALES JONES RESEARCH MARTIN SALES BLAKE SALES CLARK ACCOUNTING SCOTT RESEARCH KING123 ACCOUNTING TURNER SALES ADAMS RESEARCH ENAME DNAME ---------------------------------------- -------------- JAMES SALES FORD RESEARCH MILLER ACCOUNTING
已选择14行。
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SQL> select ename,dname 2 from dept, remoteemp 3 where remoteemp.deptno=dept.deptno; ENAME DNAME ---------------------------------------- -------------- SMITH RESEARCH ALLEN SALES WARD SALES JONES RESEARCH MARTIN SALES BLAKE SALES CLARK ACCOUNTING SCOTT RESEARCH KING123 ACCOUNTING TURNER SALES ADAMS RESEARCH ENAME DNAME ---------------------------------------- -------------- JAMES SALES FORD RESEARCH MILLER ACCOUNTING
已选择14行。
SQL> create or replace trigger sycnempsal
2 after update
3 on emp
4 for each row
5 begin
6
7 update remoteemp set sal=:new.sal where empno=:new.empno;
8
9 end;
10 /
触发器已创建
SQL> select sal from emp where empno=7839;
SAL
----------
8186
SQL> update emp set sal=sal+1 where empno=7839;
已更新 1 行。
SQL> commit;
提交完成。
SQL> select sal from emp where empno=7839;
SAL
----------
8187
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触发器应用场景三：实现数据的同步备份
只备份员工的薪水
create or replace trigger sycnempsal after update on emp for each row begin update remoteemp set sal=:new.sal where empno=:new.empno; end; /
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