14动态游标

/*
动态游标是用于执行动态SQL语句。
*/

declare
--oracle9i之前的定义
Type REFCURSOR is REF CURSOR;
cs_user REFCURSOR;

--oracle9i之后的定义
--cs_user sys_refcursor;

v_sql      varchar2(1000);
v_username varchar2(100);
v_password varchar2(100);

v_row  T_Userinfo%RowType;
v_dept T_Sys_Dept%RowType;
begin

--SQL语句的拼凑
v_username := 'a';
v_password := null;

v_sql := 'Select * From T_Userinfo where 1 = 1';
if v_username is not null and v_username != ' ' then
v_sql := v_sql || '     and username like ''%' || v_username ||
'%''       ';
end if;
if v_password is not null and v_password != ' ' then
v_sql := v_sql || ' and password = ''';
v_sql := v_sql || v_password;
v_sql := v_sql || '''';

end if;
v_sql := v_sql || ' order by userid asc';

dbms_output.put_line(v_sql);

--使用动态游标来打开动态SQL.
open cs_user for v_sql;

loop
fetch cs_user
into v_row;

if cs_user%notfound then
exit;
end if;
dbms_output.put_line(v_row.userid || '   ' || v_row.username);

end loop;

close cs_user;

dbms_output.put_line('读取另外一张表的数据');

v_sql := 'Select * From T_Sys_Dept order by dept_id asc';

open cs_user for v_sql;
loop
fetch cs_user
into v_dept;

if cs_user%notfound then
exit;
end if;
dbms_output.put_line(v_dept.dept_id || '   ' || v_dept.dept_name);
end loop;
close cs_user;
end;

--Select * From T_Userinfo where 1 = 1 order by userid asc