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What is the difference between tag and attribute in Apache IoTDB?

Time:11-25

I see it is applicable to set a tag or attribute to a timeseries, but what is the difference between these two conception?

CodePudding user response:

'Tag' of a timeseies in Apache IoTDB is indexed, which can be a filter in WHERE clause (but connnot be a part of SELECT clause for now). While 'attribute' is some kind of annotation, which cannot be filtered during a query.

For a example, in a timeserie database for electricity devices, you can set the ownership of the timeseries as a tag, so that you can query devices of a specified owner.

For more detial, you can visit this page: https://iotdb.apache.org/UserGuide/Master/IoTDB-SQL-Language/DDL-Data-Definition-Language.html#tag-and-attribute-management

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