title: What are the Limitations for Connecting to an Access Query in Excel
body: <p>I have an Access 2007 database that has a number of tables, some are fairly large (100,000+ records); I have created a <code>union query</code> to pull some of the same types of data from multiple tables into one large query for pivot table manipulation and reporting.  For example:</p>
  <pre><code>SELECT Language
  FROM Table1
  UNION ALL SELECT Language
  FROM Table2
  UNION ALL SELECT Language
  FROM Table3;
  </code></pre>
  <p>This works.  I found, quickly, however, that a <code>union query</code> will not show up when connecting to the datasource from Excel 2007.  So, I created a second query to reference the <code>union query</code>.  Like so:</p>
  <pre><code>SELECT *
  FROM [The Above Union Query];
  </code></pre>
  <p>This query works and it, initially, was accessible from Excel.  Time passed, I've added more data.  Suddenly, when I connect to my Access database from Excel my query referencing the union has disappeared.  MS Access shows no signs of an issue (data displays in Access) and my other non-union queries are showing up in Excel 2007 ... but not the one that references the union.</p>
  <h3>What could be going on?  Why did it disappear?</h3>
  <p>I noticed if I switch some of the referenced tables in the <code>union query</code> to a smaller table (with less rows) all of sudden the query appears in Excel again.  At least, I think that's what the difference is.  I really can't put my finger on why some of the <code>union queries</code> won't show up and some will.</p>
  <p>Am stumped and need some guidance.  Thanks.</p>