Oracle - 此范围内不存在名称为X的函数

Question

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:

Error(36,24): PLS-00222: no function with name 'x' exists in this scope

This is how the function looks like:

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:

messaget := testfunction(somevalue); 

where both messageT and somevalue are declared as varchar2 type.

Are cursors not allowed inside function or something like that?

Answer 1

the error would be messaget := testcursor.column1; as the cursor is closed by then (you should just use testcursorrec.column2 .

you're code isn't checking for no rows, nor duplicate rows. you can simplify this to

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;