oracle 的split函数
PL/SQL 中没有split函数,需要自己写。 代码: createorreplacetypetype_splitastableofvarchar2(50);--创建一个 type ,如果为了使split函数具有通用性,请将其size设大些。 --创建function createorreplacefunctionsplit ( p_listvarchar2, p_sepvarchar2:
PL/SQL 中没有split函数,需要自己写。
代码:
create or replace type type_split as table of varchar2(50); --创建一个 type ,如果为了使split函数具有通用性,请将其size 设大些。
--创建function
create or replace function split
(
p_list varchar2,
p_sep varchar2 := ','
) return type_split pipelined
is
l_idx pls_integer;
v_list varchar2(50) := p_list;
begin
loop
l_idx := instr(v_list,p_sep);
if l_idx > 0 then
pipe row(substr(v_list,1,l_idx-1));
v_list := substr(v_list,l_idx+length(p_sep));
else
pipe row(v_list);
exit;
end if;
end loop;
return;
end split;
测试:
SQL> select * from table(split('northsnow,塞北的雪',','));
COLUMN_VALUE
--------------------------------------------------
northsnow
塞北的雪
SQL>
补充:
-----PIPELINED关键字是什么意思?
---- pipe row是什么意思?
pipelined声名此function是pipe的,如果这么声名了,就必须使用pipe row的方式把数据返回,常规函数最后的"return 变量",就变成了"return".
pipelined的function主要是为了提高效率,不用等所有的数据都处理完成了才返回客户端,它是边处理边返回.适用于大数据量的交互.

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