JDBC API Usage: Difference between revisions

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<syntaxhighlight lang='java'>
<syntaxhighlight lang='java'>
...
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private DataSource dataSource;
private DataSource dataSource;



Revision as of 19:44, 26 September 2017

Internal

JDBC Connection Life Cycle

JDBC Connection Life Cycle

Database Metadata

The database metadata is an object that contains metadata about the database the current connection belongs to.

Connection c = ...;
DatabaseMetaData dmd = c.getMetaData();

Query

...

private DataSource dataSource;

...

Connection c;

try {

    c = dataSource.getConnection();

    PreparedStatement s = c.prepareStatement("SELECT * FROM SOME_TABLE");

    ResultSet rs = s.executeQuery();

    while(rs.next()) {

        //
        // columns are 1-based
        //

        String column1Value  = rs.getString(1);
        Long column2Value  = rs.getLong(2);

        ...
    }
}
finally {

    c.close();
}

Create

Update

Delete