我插入了使用主机名的数据。恼人的是，我即将将域从 .lan 更改为 .mydomain.com
显然我希望能够搜索我的机器的历史数据，因为它跨越了这个变化。
我可以将标签定义从 machine.lan 更新到 machine.mydomain.com 吗？
【问题讨论】：
标签： influxdb
正如其他人评论的那样，这个过程似乎是：
我今天在 python 中编写了一些辅助函数来为我做这件事，虽然我可以分享。该解决方案有点笨重，但我拥有以前的大部分功能。我相信还有其他更简洁的方法，但我找不到完整的 python 示例，所以这是我的：
主要功能：
def replace_tag(database_name:str, measurement_name:str, tag:str, old_value:str, new_value:str,):
""" Replaces an existing tag into a measurement, with a new tag for all affected records by deleting and reuploading """
# Get a dataframe of selected data
q = 'SELECT * FROM "'+ measurement_name + '"' + ' WHERE "' + tag + '" = ' + "'" + old_value + "'"
df = influx_get_read_query(query=q, database_name=database_name)
print(df)
tags_keys = influx_get_tag_keys(database_name=database_name)
field_keys = influx_get_field_keys(database_name=database_name, measurement_name=measurement_name)
# Here we collect all the new records to be written to influx
new_points = []
# Loop through each row of the returned dataframe
for i in trange(0, len(df)):
row = df.iloc[i]
print('row:', i)
row_dict = row.to_dict()
print('old row dict:', row_dict)
new_tags = {}
new_fields = {}
new_time = ''
for key in row_dict.keys():
if key in tags_keys:
new_tags[key] = row_dict[key]
elif key in field_keys:
new_fields[key] = row_dict[key]
elif key == 'time':
new_time = row_dict[key]
else:
easygui.msgbox('WARNING: A KEY WAS NOT FOUND: ' + str(key))
# Replace the old value with a new value
new_tags[tag] = new_value
new_row_dict = {}
new_row_dict['measurement'] = measurement_name
new_row_dict['tags'] = new_tags
new_row_dict['time'] = new_time
new_row_dict['fields'] = new_fields
# print('new row dict:', new_row_dict)
new_points.append(new_row_dict)
# Write the revised records back to the database
influx_write_multiple_dicts(data_dicts=new_points, database_name=database_name)
# When finished, delete all records.
influx_delete_series(database_name=database_name, measurement_name=measurement_name, tag=tag, tag_value=old_value)
其他辅助函数：
def influx_delete_series(database_name, measurement_name, tag, tag_value):
q = 'DROP SERIES FROM "' + measurement_name + '"' + ' WHERE "' + tag + '" = ' + "'" + tag_value + "'"
client = InfluxDBClient(host=HOST_ADDRESS, port=PORT, username="InfluxDB", password="Influx-DB-PASSWORD")
client.switch_database(database_name)
client.query(q, chunked=True, chunk_size=10000000000000000)
def influx_write_multiple_dicts(data_dicts:list, database_name):
"""Write a list of dicts with following structure:
database_output_influx['measurement'] = 'SENSOR_ELEMENT_SUMMARY_TEST2'
database_output_influx['tags'] = {'serialNumber':'1234', 'partNumber':'5678'}
d = datetime.now()
timestamp = d.isoformat('T')
database_output_influx['time'] = timestamp
database_output_influx['fields'] = summary_results_dict
"""
client = InfluxDBClient(host=HOST_ADDRESS, port=PORT, username="InfluxDB", password="Influx-DB-PASSWORD")
client.switch_database(database_name)
print("Return code for influx write:", client.write_points(data_dicts))
def influx_get_tag_keys(database_name):
client = InfluxDBClient(host=HOST_ADDRESS, port=PORT, username="InfluxDB", password="Influx-DB-PASSWORD")
# client.create_database('SIEMENS_ENERGY_TEST')
client.switch_database(database_name)
results = client.query("SHOW TAG KEYS ")
point_list = []
points = results.get_points()
for point in points:
point_list.append(point['tagKey'])
return point_list
def influx_get_field_keys(measurement_name, database_name):
client = InfluxDBClient(host=HOST_ADDRESS, port=PORT, username="InfluxDB", password="Influx-DB-PASSWORD")
client.switch_database(database_name)
results = client.query("SHOW FIELD KEYS FROM " + measurement_name)
point_list = []
points = results.get_points()
for point in points:
point_list.append(point['fieldKey'])
return point_list
def influx_get_read_query(query, database_name):
"""Returns a df of all measurements that have a certain field or value, for example stage. Note: single quotes for tag values, double quotes for al else. So best to use triple quotes surrounding statement. example:"""
# q = """SELECT * FROM "SENSOR_ELEMENT_TEST_CYCLE" WHERE "TestStage" = '120'"""
client = InfluxDBClient(host=HOST_ADDRESS, port=PORT, username="InfluxDB", password="Influx-DB-PASSWORD")
client.switch_database(database_name)
# print("Dataframe of all measurments of type:", measurement_name)
q = query
df = pd.DataFrame(client.query(q, chunked=True, chunk_size=10000000000000000).get_points())
# print("DF: ", tabulate(df, headers=df.columns.tolist(), tablefmt="psql"))
return df
【讨论】：
GitHub 上已经有一个开放的功能请求。 https://github.com/influxdata/influxdb/issues/4157
如果您想全部转储，修改，重新导入路径（残酷，但有效），influx 开发人员建议的可能解决方案，此评论可能会有所帮助。
https://github.com/influxdata/influxdb/issues/3904#issuecomment-268918613
【讨论】：
虽然@Michael 的回答是正确的，因为您不能通过 InfluxDB 命令更改标签值，但是您可以编写一个客户端脚本，通过在具有相同时间戳的测量中插入 "duplicate" 点来更改标签的值, fieldset 和 tagset ，除了所需的标签将更改其值。
标记错误的点（Line Protocol 格式）：
cpu,hostname=machine.lan cpu=50 1514970123
运行后
INSERT cpu,hostname=machine.mydomain.com cpu=50 1514970123
SELECT * FROM CPU 将包括
cpu,hostname=machine.lan cpu=50 1514970123
cpu,hostname=machine.mydomain.com cpu=50 1514970123
脚本运行所有 INSERT 命令后，您需要删除旧标记值的过时系列点：
DROP SERIES FROM cpu WHERE hostname='machine.lan'
当然，这是非常低效的（特别注意this bug），如果您需要将标签值更新为another tag value that other points you don't want to drop already have，您不能只使用DROP SERIES。所以请vote for InfluxDB to implement tag renaming，特别是根据WHERE 查询更改标签值。或者考虑使用允许您使用常规 SQL 的替代时间序列数据库，例如 Timescale。
【讨论】：
不幸的是，没有办法更改 InfluxDB 中历史数据的标签名称。
【讨论】：