Databases
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    <p>My advice:</p> <ul> <li><strong>Don't</strong> write a generic DAO; Generic classes come back to bite you when you realise they don't quite do what you need in a specific situation and often end up growing in complexity to cover the ever-increasing array of use-cases. Better to code application specific DAOs and then attempt to generify any common behaviour later on.</li> <li>Consider using <a href="http://static.springsource.org/spring/docs/2.0.x/reference/jdbc.html" rel="nofollow noreferrer">Spring JDBC</a> to write app-specific DAOs but in a much more compact and less error-prone fashion than JDBC. Also, unlike Hibernate, Spring JDBC only acts a thin wrapper around raw JDBC giving you finer grained control and more visibility.</li> </ul> <p><strong>Example</strong></p> <pre><code>// Create or inject underlying DataSource. DataSource ds = ... // Initialise Spring template, which we'll use for querying. SimpleJdbcTemplate tmpl = new SimpleJdbcTemplate(ds); // Create collection of "Role"s: The business object we're interested in. Set&lt;Role&gt; roles = new HashSet&lt;Role&gt;(); // Query database for roles, use row mapper to extract and create // business objects and add to collection. If an error occurs Spring // will translate the checked SQLException into an unchecked Spring // DataAccessException and also close any open resources (ResultSet, Connection). roles.addAll(tmpl.query("select * from Role", new ParameterizedRowMapper&lt;Role&gt;() { public Role mapRow(ResultSet resultSet, int i) throws SQLException { return new Role(resultSet.getString("RoleName")); } })); </code></pre>
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    1. COAnother vote for Spring JDBC. It handles a lot of the boilerplate connection stuff (to avoid resource leaks). In addition, it provides a much nicer way of mapping columns to your objects. One other comment, I wouldn't hard-code the primary key column name. As soon as you do that, someone comes along a creates a table with a column named something else, or uses a multi-column primary key.
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Guidance
A row detail

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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