PLS-00201 identifier must be declared

PLS-00201 identifier must be declared

Oracle SQL Error: PLS-00201 identifier must be declared

Cause:

An attempt was made to reference either an undeclared variable, exception, procedure, or other item, or an item to which no privilege was granted or an item to which privilege was granted only through a role.




Solution:

Check your spelling and declaration of the referenced name.
Verify that the declaration for the referenced item is placed correctly in the block structure.
Check the referenced item privileges.

Example:

DECLARE
BEGIN
	SELECT name INTO v_name 
	FROM BOOKS WHERE id=1;
	DBMS_OUTPUT.PUT_LINE(v_name);
END;

Output:

ORA-06550: line 3, column 19:
PLS-00201: identifier ‘V_NAME’ must be declared
ORA-06550: line 4, column 2:
PL/SQL: ORA-00904: : invalid identifier

Correct

DECLARE
v_name varchar2(250);
BEGIN
	SELECT name INTO v_name 
	FROM BOOKS WHERE id=1;
	DBMS_OUTPUT.PUT_LINE(v_name);
END;

Output:

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