get_zd3(a.c4)
from t_1 a;
create or replace function get_zd1(code in varchar2) return varchar2 is
Result varchar2(50);
begin
select c into Result from t_zdwhere'A'||code=dm;
return(Result);
end get_zd1;
create or replace function get_zd2(code in varchar2) return varchar2 is
Result varchar2(50);
begin
select c into Result from t_zdwhere'B'||code=dm;
return(Result);
end get_zd2;
create or replace function get_zd3(code in varchar2) return varchar2 is
Result varchar2(50);
begin
select c into Result from t_zd where'C'||code=dm;
return(Result);
end get_zd3;
我知道这样混合使用sql与pl/sql的效率会降低，请教如何用一个sql语句完成同样的功能？
