title: Why do I get the error: Column part of using cannot have a qualifier
body: <p>This is the query I am trying to run: </p>
  
  <pre><code>select
     ordervariety,
     bat.batch,
     order_date,
     var.variety,
     var.the_name,
     bat.the_name,
     var.the_price,
     bat.the_price
     quantity
  from
     test_orders
     join TEST_ORDERVARIETIES using (orderno)
     full outer join assessment_varieties var using (variety)
     full outer join test_batches bat using (batch)
  where
     ordervariety is not null
  </code></pre>
  
  <p>The tables are structured as follows:
  TEST_ORDERS:</p>
  
  <pre><code>Column Name Data Type   Nullable    Default Primary Key
  ORDERNO NUMBER(6,0) No  -   1
  SHOP    NUMBER(3,0) No  -   -
  ORDER_DATE  DATE    No  -   -
  </code></pre>
  
  <p>TEST_ORDERVARIETIES:</p>
  
  <pre><code>ORDERVARIETY    NUMBER(6,0) No  -   1
  ORDERNO NUMBER(6,0) No  -   -
  VARIETY NUMBER(6,0) Yes -   -
  BATCH   NUMBER(6,0) Yes -   -
  QUANTITY    NUMBER(3,0) No  -   -
  </code></pre>
  
  <p>TEST_BATCHES:</p>
  
  <pre><code>Column Name Data Type   Nullable    Default Primary Key
  BATCH   NUMBER(6,0) No  -   1
  GREENHOUSE  NUMBER(3,0) No  -   -
  THE_NAME    VARCHAR2(50)    No  -   -
  VARIETY NUMBER(3,0) No  -   -
  THE_PRICE   NUMBER(5,2) Yes -   -
  </code></pre>
  
  <p>ASSESSMENT_VARIETIES:</p>
  
  <pre><code>Column Name Data Type   Nullable    Default Primary Key
  VARIETY NUMBER(6,0) No  -   1
  SPECIES NUMBER(6,0) No  -   -
  THE_NAME    CHAR(64)    Yes -   -
  THE_PRICE   NUMBER(8,2) Yes -   -
  THE_GROWING_NOTES   CHAR(255)   Yes -   -
  </code></pre>
  
  <p>Why do I get the error: ORA-25154: column part of USING clause cannot have qualifier?</p>
  
  <p>And what can I do to fix it? Thank you!</p>