OceanBase 数据库支持JDBC驱动连接。经常有人问怎么连接，这里就简单说明一下。

驱动用法

driver=com.alipay.oceanbase.obproxy.mysql.jdbc.Driverconn=jdbc:oceanbase://127.1:2883/tpcc?useUnicode=true&characterEncoding=utf-8&rewriteBatchedStatements=true&allowMultiQueries=trueuser=tpcc@oboracle#obdemopassword=123456

        BasicDataSource dataSource = new BasicDataSource();        dataSource.setDriverClassName("com.alipay.oceanbase.jdbc.Driver");        dataSource.setUrl("jdbc:oceanbase://" + ip + ":" + port + "/" + dbName + "?rewriteBatchedStatements=true&allowMultiQueries=true&useLocalSessionState=true&useUnicode=true&characterEncoding=utf-8&socketTimeout=3000000&userAffectedRows=true");        dataSource.setUsername(user);        dataSource.setPassword(passwd);        dataSource.setMaxIdle(6000);        dataSource.setMaxActive(6000);        dataSource.setPoolPreparedStatements(true);        dataSource.setMaxOpenPreparedStatements(60000);

PreparedStatement
 用法

//DBStatement dbst = new DBStatement(connection);try {    PreparedStatement pstmt = connection.prepareStatement(sql);    try {        ResultSet rs = pstmt.executeQuery();        try {            List<MemRow> rows = getRows(rs, rs.getMetaData());            if (toCache) {                setCache(rows);            } else {                setRows(rows);            }        } finally {            rs.close();        }    } catch (SQLNonTransientConnectionException | SQLRecoverableException e) {        throw e;    } catch (Exception e) {        Error.raise(RBPM_CORE_0010, viewName, sql, e.getMessage());    } finally {        pstmt.close();    }} finally {
    //dbst.close();
}

CallableStatement
 用法

public class MainCall {    public static void main(String[] args) {        try {            Driver driver = new com.alipay.oceanbase.jdbc.Driver();            Properties p = new Properties();            p.setProperty("", "");            Connection conn = DriverManager.getConnection("jdbc:oceanbase://127.1:2883/bankcore",                    "bankcore@oboracle#obdemo", "123456");            // Create PROCEDURE 'calc_add'            Statement stmt = conn.createStatement();            String sql = "create or replace PROCEDURE calc_add(a1 IN int, a2 IN OUT int) is "                    + "begin " + "  a2:=a1+a2; " + "end;";            stmt.execute(sql);            //Execute PROCEDURE 'calc_add'            CallableStatement csmt = conn.prepareCall("call calc_add(?, ?)");            csmt.setInt(1, 1);            csmt.setInt(2, 2);            csmt.registerOutParameter(2, Types.INTEGER);            csmt.execute();            //Get Result of a2 from 'calc_add'            int sum = csmt.getInt(1);            System.out.println("sum:" + sum);        } catch (SQLException e) {            e.printStackTrace();        }    }}

其他建议

• 使用连接池技术，连接池注意设置 keepAlive 属性
  ，即避免空闲连接。连接空闲太久可能会被 OB 或者网络上其他设备中断。

• 数据库操作要有异常处理逻辑。如果是连接中断，则新建连接；如果是事务异常，则回滚事务。事务长期不提交很容易触发 OB 的事务未提交超时或者空闲超时机制。如果是事务未提交超时，该连接必须明确发起 commit
   或 rollback
  以清理连接的事务状态。否则这个连接不能再使用（会报事务超时错误）。

参考

• 从ORACLE/MySQL到OceanBase：数据库超时机制