显式游标_cursor is_open_fetch_close
scott>--显式游标(定义_打开_提取_关闭)
scott>declare
2 cursor c_emp is select ename from emp;
3 v_ename emp.ename%type;
4 begin
5 open c_emp;
6 fetch c_emp into v_ename;
7 dbms_output.put_line(v_ename);
8 close c_emp;
9 end;
10 /
scott>declare
2 cursor c_emp is select ename from emp;
3 v_ename emp.ename%type;
4 begin
5 open c_emp;
6 fetch c_emp into v_ename;
7 dbms_output.put_line(v_ename);
8 close c_emp;
9 end;
10 /
PL/SQL procedure successfully completed.
scott>set serveroutput on
scott>r
1 declare
2 cursor c_emp is select ename from emp;
3 v_ename emp.ename%type;
4 begin
5 open c_emp;
6 fetch c_emp into v_ename;
7 dbms_output.put_line(v_ename);
8 close c_emp;
9* end;
SMITH
scott>r
1 declare
2 cursor c_emp is select ename from emp;
3 v_ename emp.ename%type;
4 begin
5 open c_emp;
6 fetch c_emp into v_ename;
7 dbms_output.put_line(v_ename);
8 close c_emp;
9* end;
SMITH
说明游标一下子就只取一条记录，好慢哟
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/9240380/viewspace-666587/ ，如需转载，请注明出处，否则将追究法律责任。
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