Example 2-16 Scope Rules

DECLARE
   a CHAR;
   b REAL;
BEGIN
   -- identifiers available here: a (CHAR), b
   DECLARE
      a INTEGER;
      c REAL;
   BEGIN
     NULL; -- identifiers available here: a (INTEGER), b, c
   END;
   DECLARE
      d REAL;
   BEGIN
     NULL; -- identifiers available here: a (CHAR), b, d
   END;
   -- identifiers available here: a (CHAR), b
END;
/

Example 2-16 Scope Rules

DECLARE
   a CHAR;
   b REAL;
BEGIN
   -- identifiers available here: a (CHAR), b
   DECLARE
      a INTEGER;
      c REAL;
   BEGIN
     NULL; -- identifiers available here: a (INTEGER), b, c
   END;
   DECLARE
      d REAL;
   BEGIN
     NULL; -- identifiers available here: a (CHAR), b, d
   END;
   -- identifiers available here: a (CHAR), b
END;
/