PLS-00201：必须声明标识符“ D”

Question

Please check my procedure. I got error when I tried to pass string to procedure. It worked fine if I pass number.

DECLARE 
    x   number(2);
    name    varchar2(333);
    PROCEDURE hello(id IN OUT Number, name in varchar2)
    IS
        i number(2):= 1;
        mName   varchar2(3000):='jjjj';
    BEGIN
        dbms_output.put_line('This line is in procedure'); 
        while i < id
        loop
            mName:= '' || ' ohlla';         
            dbms_output.put_line('Id is ' || i ||  ' name ' || mName );
            i:=i+1;
        end loop;
    END;
BEGIN
    x := &id;
    name:= &somename;   
    hello(x, name);
    dbms_output.put_line('Last line is id= ' || x || ' Finished ' );

END;
/

Answer 1

You are missing quotes in assignment to a string variable; try:

name:= '&somename';

This way it will work with numeric IDs and literal names; if you need literal IDs, you need to change the type of variable x and add quotes in the assignment to x too.

Answer 2

The preferred solution is to make the change suggested by Aleksej in your code (put quotes around &somename in the assignment).

A workaround, which you may need if you can't change the procedure (for example if you don't own it, or if other procedures may depend on this one and they may break if you make changes - even if the change is to make THIS procedure better) is to pass the string to the procedure WITH QUOTES, like so:

SQL> enter value for &somename: 'mary'

Substitution variables are substituted verbatim, so you need the quotes for a varchar2 (in one and only one place, either in the code or in the assignment to the substitution variable &somename, outside the procedure).

Is this an actual procedure you wrote or are you using it just as an example? I ask because I didn't see where you use the input variable "name" in the inner procedure.

And, to clarify the error message: If you pass mary (with no quotes), when compilation gets to the offending assignment, the compiler assumes mary is the name of another variable (since is not a character literal); but it knows of no variable named mary, so it raises the exception you saw. The compiler doesn't guess correctly at what the actual error is (missing quotes).