如何获取时间序列数据库的最新记录？

发布于 2025-01-16 16:27:53 字数 1695 浏览 0 评论 0原文

我有一个只有三列的时间序列数据库。第一列用于 id，第二列用于时间戳，第三列用于 iOT 的输出。我正在我的 Ubuntu 机器上运行 griddb python 客户端。我需要从数据库中获取最新的记录。最新记录应该是在查询运行当天刚刚添加的记录。无论是 SQL 查询还是函数，我只需要一种方法让它工作。以下是我在 GridDB 容器中存储时间序列数据库的方式以及数据库的概述。

python

##...
factory = griddb.StoreFactory.get_instance()

## Initializing the container
try:
    gridstore = factory.get_store(host="127.0.0.1",
                                  port=59111,
                                  cluster_name="cluster_one",
                                  username="admin",
                                  password="")
    conInfo = griddb.ContainerInfo("iOT_Project",
                    [["id", griddb.Type.INTEGER],
                     ["time_stamp", griddb.Type.TIMESTAMP],
                     ["output", griddb.Type.FLOAT]],
                    griddb.ContainerType.COLLECTION, True)
    container = gridstore.put_container(conInfo)
    
    ## Reading the database with pandas
    data = pd.read_csv("database.csv")

    ## Adding the database to the container
    for i in range(len(data)):
        ret = container.put(data.iloc[i, :])
    print("Data added successfully")


except Exception as e:
    print("Error: ", e)

iot_database

id	time_stamp	输出
232	01/01/2019 11:20	85309.52
233	02/01/2019 12:52	6398.54
234	03/01/2019 23:45	97583.63
235	04/01/2019 22:21	86533.11
236	2019年5月1日 13:42	12421.35

原文

I have a time series database with just three columns. The first column is for the id, the second is for the time stamps, and the third column is for the output of the iOT.
I am running the griddb python client on my Ubuntu machine. I need to get the most recent records from the database. The most recent records should be the ones just added on the day the query is run.
Whether it’s an SQL query or a function, I just need a way to make it work.
Here is how I stored the timeseries database in my GridDB container and an overview of the database.

python

##...
factory = griddb.StoreFactory.get_instance()

## Initializing the container
try:
    gridstore = factory.get_store(host="127.0.0.1",
                                  port=59111,
                                  cluster_name="cluster_one",
                                  username="admin",
                                  password="")
    conInfo = griddb.ContainerInfo("iOT_Project",
                    [["id", griddb.Type.INTEGER],
                     ["time_stamp", griddb.Type.TIMESTAMP],
                     ["output", griddb.Type.FLOAT]],
                    griddb.ContainerType.COLLECTION, True)
    container = gridstore.put_container(conInfo)
    
    ## Reading the database with pandas
    data = pd.read_csv("database.csv")

    ## Adding the database to the container
    for i in range(len(data)):
        ret = container.put(data.iloc[i, :])
    print("Data added successfully")


except Exception as e:
    print("Error: ", e)

iot_database