Oracle - 此范围内不存在名称为 X 的函数
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Oracle - no function with name X exists in this scope
提问by user1831003
The function is clearly there, because I can navigate to it using SQL Developer and it compiles all fine, but when I try to use the function with or without "call", it throws:
该函数显然在那里，因为我可以使用 SQL Developer 导航到它并且编译一切正常，但是当我尝试使用带有或不带有“调用”的函数时，它会抛出：
Error(36,24): PLS-00222: no function with name 'x' exists in this scope
错误（36,24）：PLS-00222：此范围内不存在名称为“x”的函数
This is how the function looks like:
这是函数的样子：
create or replace function testfunction
(
somevalue in varchar2
)
return varchar2
AS
cursor testcursor IS
select column1, column2 from table1 t
where t.column1 = somevalue;
testcursorrec testcursor %rowtype;
messaget VARCHAR2(500);
begin
open testcursor ;
fetch testcursor into testcursorrec ;
close testcursor ;
messaget := testcursor.column1;
return messaget ;
end;
This is how I'm calling it:
我是这样称呼它的：
messaget := testfunction(somevalue);
where both messageT and somevalue are declared as varchar2 type.
其中 messageT 和 somevalue 都声明为 varchar2 类型。
Are cursors not allowed inside function or something like that?
函数内部是否不允许使用游标或类似的东西？
回答by DazzaL
the error would be messaget := testcursor.column1;as the cursor is closed by then (you should just use testcursorrec.column2.
错误将是messaget := testcursor.column1;因为到那时光标已关闭（您应该只使用testcursorrec.column2.
you're code isn't checking for no rows, nor duplicate rows. you can simplify this to
你的代码没有检查没有行，也没有检查重复的行。您可以将其简化为
create or replace function testfunction
(
somevalue in table1.column1%type
)
return table1.column2%type
AS
messaget table1.column2%type; -- use %type where possible.
begin
select t.column2
into messaget
from table1 t
where t.column1 = somevalue
and rownum = 1;--only if you dont care if theres 2+ rows.
return messaget;
exception
when no_data_found
then
return null; -- if you want to ignore no rows.
end;
