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    <p>If every row should get a different value that cannot be derived from the existing data in the database, there is not much you can do to optimize the overall complexity. So do not expect too much wonders.</p> <p>That said, you should start using prepared statements and batching:</p> <pre><code>public void updateRank(Map&lt;Integer,Double&gt; map){ Iterator&lt;Entry&lt;Integer, Double&gt;&gt; it = map.entrySet().iterator(); String query = ""; int i = 0; Connection connection = getConnection(); // get the DB connection from somewhere PreparedStatement stmt = connection.prepareStatement("update profile set rank = ? where profileId = ?"); while (it.hasNext()) { Map.Entry&lt;Integer,Double&gt; pairs = (Map.Entry&lt;Integer,Double&gt;)it.next(); stmt.setInt(1, pairs.getValue()); stmt.setDouble(2, pairs.getKey()); stmt.addBatch(); // this will just collect the data values it.remove(); } stmt.executeBatch(); // this will actually execute the updates all in one } </code></pre> <p>What this does:</p> <ol> <li>the prepared statement causes the SQL parser to only parse the SQL once</li> <li>the batching minimizes the client-server-roundtrips so that not one for every update</li> <li>the communication between client and server is minimized because the SQL is only transmitted once and the data is collected and sent as a packet (or at least fewer packets)</li> </ol> <p>In addition:</p> <ul> <li>Please check if the database column <code>profileId</code> is using an index so that looking up the respective row is fast enough</li> <li>You could check if your connection is set to auto-commit. If so try to disable auto-commit and explicitly commit the transaction after all rows are updated. This way the single update operations could be faster as well.</li> </ul>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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