title: SQL invalid identifier
body: <p>I checked some of the SQL invalid identifier solutions, but none of them helped me to fix my prob.</p>
  
  <pre><code>CREATE OR REPLACE PROCEDURE add_order(
    p_cust_id       cust_order.cust_id%TYPE,
    p_order_id      cust_order.order_id%TYPE,
    p_order_date    cust_order.order_date%TYPE,
    p_sales_made_by cust_order.sales_made_by%TYPE,
    p_qty           cust_order.qty%TYPE,
    p_product_id    cust_order.product_id%TYPE,
    p_cust_charged  cust_order.cust_charged%TYPE,
    p_company_price cust_order.company_price%TYPE,
    p_shipper_id    cust_order.shipper_id%TYPE)
  IS
    BEGIN
      IF p_shipper_id = 'FEDEX' OR p_shipper_id = 'USPS' OR p_shipper_id = 'CUST' THEN
  
        INSERT INTO productss (cust_id, order_id, order_date, sales_made_by, qty,
                               product_id, cust_charged, company_price, shipper_id)
        VALUES (p_cust_id, p_order_id, p_order_date, p_sales_made_by, p_qty,
                p_product_id, p_cust_charged, p_company_price, p_shipper_id);   
  
      ELSE
        dbms_output.PUT_LINE('This shipper IS NOT allowed');
      END IF;
    END add_order;
  /
  </code></pre>
  
  <p>The error is:</p>
  
  <pre><code>   17/1     PL/SQL: SQL Statement ignored
     17/116   PL/SQL: ORA-00904: "SHIPPER_ID": invalid identifier
  </code></pre>
  
  <p>This is the table:</p>
  
  <pre><code>   CREATE TABLE CUST_ORDER
     (
    CUST_ID        NUMBER(15),
    ORDER_ID       NUMBER(20),
    ORDER_DATE     DATE,
    SALES_MADE_BY  VARCHAR(40),
    QTY            NUMBER,
    PRODUCT_ID     NUMBER,
    CUST_CHARGED   NUMBER,
    COMPANY_PRICE  NUMBER,
    SHIPPER_ID     NUMBER,
    PRIMARY KEY (ORDER_ID),
    FOREIGN KEY (CUST_ID) REFERENCES CUST_INFO(CUST_ID),
    FOREIGN KEY (PRODUCT_ID) REFERENCES PRODUCTS(PRODUCT_ID)
    FOREIGN KEY (SHIPPER_ID) REFERENCES SHIPPING(SHIPPER_ID)
   );
  </code></pre>
  
  <p>I guess that it is obvious mistake, but I was working too much.</p>