用PL/SQL写程序实现如
set serveroutput ondeclare
t varchar2(1000);
begin
for v_cur in (select dname from dept where deptno>0) loop
t:=t||v_cur.dname;
end loop;
dbms_output.put_line(t);
end;
/
set serveroutput ondeclare
t varchar2(1000);
begin
for v_cur in (select dname from dept where deptno>0) loop
t:=t||v_cur.dname;
end loop;
dbms_output.put_line(t);
end;
/
return varchar2 is
Result varchar2(100);
cursor rad_cursor(v_id varchar2) is
select distinct name from student
where id=v_id ;
begin for v_sor in rad_cursor(p_id) loop
Result:=Result||v_sor.name;
end loop;
return(Result);
end get_book;
/select id,get(id) from student group by id;
select 变量1 = 变量 + 字段1 from 表名 where 条件
变量1 := '';
select 变量1 = 变量 || 字段1 from 表名 where 条件
省时,方便,价格便宜,量又足