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/**
 * 方案一：
 * 使用select * from table where order by 进行查询，但是使用默认方式
 */
private void plan1(String startTime, String endTime) {
    StringBuilder queryBuilder = new StringBuilder("select * from ")
            .append(jdbcUtils.getTableName())
            .append(" where ")
            .append(jdbcUtils.getFieldArray()[2]).append(" >= ? and ").append(jdbcUtils.getFieldArray()[2])
            .append(" <= ? order by ").append(jdbcUtils.getFieldArray()[2]).append(" asc");
    long start = System.currentTimeMillis();
    long startUsedMemory = memoryMonitor.getUsedMemory();
    try (Connection connection = jdbcUtils.getJdbcTemplate().getDataSource().getConnection()) {
        PreparedStatement ps = connection.prepareStatement(queryBuilder.toString());
        ps.setObject(1, startTime);
        ps.setObject(2, endTime);
        ResultSet rs = ps.executeQuery();
        log.info("plan1 consumed {}, {}", TimeUtils.humanizedFormat(System.currentTimeMillis(), start),
                memoryMonitor.convertBytes(memoryMonitor.getUsedMemory() - startUsedMemory));
    } catch (Exception ignore) {
    }
}

/**
 * 方案二：
 * 使用select * from table where order by 进行查询，但是使用参数调优
 */
private void plan2(String startTime, String endTime) {
    StringBuilder queryBuilder = new StringBuilder("select * from ")
            .append(jdbcUtils.getTableName())
            .append(" where ")
            .append(jdbcUtils.getFieldArray()[2]).append(" >= ? and ").append(jdbcUtils.getFieldArray()[2])
            .append(" <= ? order by ").append(jdbcUtils.getFieldArray()[2]).append(" asc");
    long start = System.currentTimeMillis();
    long startUsedMemory = memoryMonitor.getUsedMemory();
    try (Connection connection = jdbcUtils.getJdbcTemplate().getDataSource().getConnection()) {
        //对于postgresql，只有关闭事务，setFetchSize才会生效
        connection.setAutoCommit(false);
        //对于postgresql，后面的两个参数其实也就是默认值时使用的
        PreparedStatement ps = connection.prepareStatement(queryBuilder.toString(), ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
        ps.setFetchSize(1000);
        ps.setFetchDirection(ResultSet.FETCH_FORWARD);
        ps.setObject(1, startTime);
        ps.setObject(2, endTime);
        ResultSet rs = ps.executeQuery();
        log.info("plan2 consumed {}, {}", TimeUtils.humanizedFormat(System.currentTimeMillis(), start),
                memoryMonitor.convertBytes(memoryMonitor.getUsedMemory() - startUsedMemory));
    } catch (Exception ignore) {
    }
}