This is a fully working application that polls a BMP280 and SHT40 MEMS sensors over I2C, samples are queued, and then transmitted to a MACHBASE instance that resides on a local network. The device connects to the local network over WIFI, synchronizes the system clock through SNTP services, and publishes data to the MACHBASE MQTT broker at a 3-second interval.
See 'network_connect.c' for WIFI and MQTT connection configuration parameters. Just ensure that the 'NET_DEVICE_ID' matches the 'MQTT_BROKER_CLIENT_ID' and that you are publishing to the correct 'topic'. See MACHBASE helpfiles but it is basically the database name that you create.
For this example, all have to do is create a 'TAG' table with the following columns: NAME (varchar 150), TIMESTAMP (datetime), VALUE (double), PARAMETER (varchar 100), and DEVICE_ID (varchar 50). The MQTT message format published to MACHBASE over MQTT looks like the following:
["ca.nb.01-1000.Air-Temperature",1729957661187888000,1002.928162,"Air-Temperature", "ca.nb.aws.01-1000"]
Likewise, lookup tables can be created as well for category or code based parameters. See 'SQL_[name]_Create.sql' files for more information.
MACHBASE is a time-series database that is designed to manage temporal data, needless to say, it is ideal for Internet of Things (IoT) use-cases and can handle highspeed sampling (e.g., much faster than a 3-second interval). Time-series databases are relatively new, commercially available, and are amazingly faster than legacy relational databases. MACHBASE has some of the highest performance metrics in the industry and they offer it as a community based release but you do have to buy a license for commercial use-cases. However, if you enjoy tinkering and looking to store and visualize your data, then look no further and give MACHBASE a try. MACHBASE is loaded with features for both data manipulation, transformation, management and visualization, and much more. It leverages Apache eCharts and they offer a language called TQL that is out of this world for data scientists or data engineers but even the average joe can build impressive charts to showcase your work.
I plan to post more MACHBASE examples once I have them completed. Their help files are okay but if you are like myself, I learn from real world examples i.e. applied, and will share what I can shortly. If you have any questions or would like to contribute feel free to conact me.
Copyright (c) 2024 Eric Gionet ([email protected])