title: BigQuery Arrays - check if Array contains specific values
body: <p>I'm trying to see if a certain set of items exist within a BigQuery Array. <br></p>
  <p>Below query works (Checking if a 1 item exists within an array):</p>
  <pre class="lang-sql prettyprint-override"><code>WITH sequences AS
  (
      SELECT 1 AS id, [10,20,30,40] AS some_numbers
          UNION ALL 
      SELECT 2 AS id, [20,30,40,50] AS some_numbers
          UNION ALL 
      SELECT 3 AS id, [40,50,60,70] AS some_numbers
  )
  SELECT id, some_numbers 
  FROM sequences 
  WHERE 20 IN UNNEST(some_numbers)
  </code></pre>
  <br>
  <p>What I'm not able to do is below (Checking if a more than 1 item exists within an array):</p>
  <p>(This query errors)</p>
  <pre class="lang-sql prettyprint-override"><code>WITH sequences AS
  (
      SELECT 1 AS id, [10,20,30,40] AS some_numbers
          UNION ALL 
      SELECT 2 AS id, [20,30,40,50] AS some_numbers
          UNION ALL 
      SELECT 3 AS id, [40,50,60,70] AS some_numbers
  )
  SELECT id, some_numbers 
  FROM sequences 
  WHERE (20,30) IN UNNEST(some_numbers)
  </code></pre>
  <br>
  I managed to find below workaround, but I feel there's a better way to do this:
  <pre class="lang-sql prettyprint-override"><code>WITH sequences AS
  (
      SELECT 1 AS id, [10,20,30,40] AS some_numbers
          UNION ALL 
      SELECT 2 AS id, [20,30,40,50] AS some_numbers
          UNION ALL 
      SELECT 3 AS id, [40,50,60,70] AS some_numbers
  )
  
  SELECT id, some_numbers  
  FROM  sequences
  WHERE (
      
      ( 
          SELECT COUNT(1)
          FROM UNNEST(some_numbers) s
          WHERE s in (20,30)
      ) &gt; 1
  )
  </code></pre>
  <p>Any suggestions are appreciated.</p>