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    <p>I have run into the same frustrating issue. Sometimes the <code>AS</code> keyword would have its intended effect, but other times it wouldn't. I was unable to identify the conditions to make it work correctly.</p> <p><strong>Short Answer:</strong> (Thanks to Simon Urbanek (package maintainer for RJDBC), Yev, and Sebastien! See the <strong>Long Answer.</strong>) One thing that you may try is to open your JDBC connection using <code>?useOldAliasMetadataBehavior=true</code> in your connection string. Example:</p> <pre><code>drv &lt;- JDBC("com.mysql.jdbc.Driver", "C:/JDBC/mysql-connector-java-5.1.18-bin.jar", identifier.quote="`") conn &lt;- dbConnect(drv, "jdbc:mysql://server/schema?useOldAliasMetadataBehavior=true", "username", "password") query &lt;- "SELECT `a` AS `b` FROM table" result &lt;- dbGetQuery(conn, query) dbDisconnect(conn) </code></pre> <p>This ended up working for me! See more details, including caveats, in the <strong>Long Answer.</strong></p> <p><strong>Long Answer:</strong> I tried all sorts of stuff, including making views, changing queries, using JOIN statements, NOT using JOIN statements, using ORDER BY and GROUP BY statements, etc. I was never able to figure out why some of my queries were able to rename columns and others weren't.</p> <p>I contacted the package maintainer (Simon Urbanek.) Here is what he said:</p> <blockquote> <p>In the vast majority of cases this is an issue in the JBDC driver, because there is really not much RJDBC can do other than to call the driver.</p> </blockquote> <p>He then recommended that I make sure I had the most recent JDBC driver for MySQL. I did have the most recent version. However, it got me thinking "maybe it IS a bug with the JDBC driver." So, I searched Google for: <code>mysql jdbc driver bug alias</code>.</p> <p>The top result for this query was <a href="http://bugs.mysql.com/bug.php?id=33966">an entry at bugs.mysql.com</a>. Yev, using MySQL 5.1.22, says that when he upgraded from driver version 5.0.4 to 5.1.5, his column aliases stopped working. Asked if it was a bug.</p> <p>Sebastien replied, "No, it's not a bug! It's a documented change of behavior in all subsequent versions of the driver." and suggested using <code>?useOldAliasMetadataBehavior=true</code>, citing <a href="http://dev.mysql.com/doc/refman/5.1/en/connector-j-reference-configuration-properties.html">documentation for the JDBC driver</a>.</p> <p><strong>Caveat Lector:</strong> The documentation for the JDBC driver states that </p> <blockquote> <p>useColumnNamesInFindColumn is preferred over useOldAliasMetadataBehavior unless you need the specific behavior that it provides with respect to ResultSetMetadata.</p> </blockquote> <p>I haven't had the time to fully research what this means. In other words, I don't know what all of the ramifications are of using <code>useOldAliasMetadataBehavior=true</code> are. Use at your own risk. Does someone else have more information?</p>
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