使用java.sql.ResultSet是否有一种方法通过使用列的索引来获得列名作为字符串?我看了API文档,但什么都没找到。


当前回答

SQLite 3

教科书getMetaData ();

DatabaseMetaData md = conn.getMetaData();
ResultSet rset = md.getColumns(null, null, "your_table_name", null);

System.out.println("your_table_name");
while (rset.next())
{
    System.out.println("\t" + rset.getString(4));
}

编辑:这也适用于PostgreSQL

其他回答

除了上面的答案,如果您正在使用一个动态查询,并且您想要列名,但不知道有多少列,您可以使用ResultSetMetaData对象首先获得列的数量,然后循环遍历它们。

修改Brian的代码:

ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
int columnCount = rsmd.getColumnCount();

// The column count starts from 1
for (int i = 1; i <= columnCount; i++ ) {
  String name = rsmd.getColumnName(i);
  // Do stuff with name
}

SQLite 3

教科书getMetaData ();

DatabaseMetaData md = conn.getMetaData();
ResultSet rset = md.getColumns(null, null, "your_table_name", null);

System.out.println("your_table_name");
while (rset.next())
{
    System.out.println("\t" + rset.getString(4));
}

编辑:这也适用于PostgreSQL

U可以从resultSet.getMetaData()获取列名和值; 这段代码为我工作:

Connection conn = null;
PreparedStatement preparedStatement = null;
    try {
        Class.forName("com.mysql.cj.jdbc.Driver");
        conn = MySQLJDBCUtil.getConnection();
        preparedStatement = conn.prepareStatement(sql);
        if (params != null) {
            for (int i = 0; i < params.size(); i++) {
                preparedStatement.setObject(i + 1, params.get(i).getSqlValue());
            }
            ResultSet resultSet = preparedStatement.executeQuery();
            ResultSetMetaData md = resultSet.getMetaData();
            while (resultSet.next()) {
                int counter = md.getColumnCount();
                String colName[] = new String[counter];
                Map<String, Object> field = new HashMap<>();
                for (int loop = 1; loop <= counter; loop++) {
                    int index = loop - 1;
                    colName[index] = md.getColumnLabel(loop);
                    field.put(colName[index], resultSet.getObject(colName[index]));
                }
                rows.add(field);
            }
        }
    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        if (preparedStatement != null) {
            try {
                preparedStatement.close();
            }catch (Exception e1) {
                e1.printStackTrace();
            }
        }
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    return rows;

如果你想使用spring jdbctemplate并且不想处理连接人员,你可以使用以下方法:

jdbcTemplate.query("select * from books", new RowCallbackHandler() {
        public void processRow(ResultSet resultSet) throws SQLException {
            ResultSetMetaData rsmd = resultSet.getMetaData();
            for (int i = 1; i <= rsmd.getColumnCount(); i++ ) {
                String name = rsmd.getColumnName(i);
                // Do stuff with name
            }
        }
    });

我知道,这个问题已经回答了,但可能像我这样的人需要通过标签而不是索引访问DatabaseMetaData的列名:

ResultSet resultSet = null;
DatabaseMetaData metaData = null;

    try {
        metaData  = connection.getMetaData();
        resultSet = metaData.getColumns(null, null, tableName, null);

        while (resultSet.next()){
            String name = resultSet.getString("COLUMN_NAME");
        }
    }