Cumulus Support

I am having a difficult time deciding which devices I should purchase to automatically send data from my Davis Pro2 personal weather station into a time series database so that I can view the data with data visualization tools. I have read a lot about installing a tool called weewx onto a raspberry pi, but I don't know what device I should actually purchase and what cords I need along with it. I don't know very much about raspberry pi devices but I can follow directions.

Different pieces of hardware I have read about include a raspberry pi, Meteo-Pi ("a connectivity device to allow you to connect your favorite Davis® weather station to Raspberry Pi mini computer"), Davis USB logger, meteobridge, Belfryboy Clone USB logger, CumulusMX, weewx, , or wifilogger2.

First off CumulusMX will do what you want as far as database, and will also do more, can't comment on weewx as I never used it, these are 2 different software programs that retrieve and store your data. Now what you need for either program to work would be A computer or RassPI and at least the davis usb logger, this will allow you to connect via usb to your computer to process the data, it will also store data if your system goes down.
As far as the other devices listed are concerned, they are not needed, but may help in connecting your computer to it as something like the meteobridge will allow for network connection to retrieve the data. There is also the davis weatherlink live you can use instead of the usb logger but there can be subscription costs involved for up to the minute history.
Maybe someone can comment on the wifilogger and the belfryboy devices for you best informed decision on what to use.
For the raspberry PI there is an image put out by the developers here or you can use the stock distro with the pi and there are plenty of documents on how to set it all up in the wiki either way. and very helpful people here to help you out.

With the Davis you can have either the console/Envoy or Weatherlink Live, or both, receiving from your VP2 or Vue ISS. With the console/Envoy you can use either the USB, serial, or WiFiLogger logger and CumulusMX can work with any of these 3 loggers, but you can run only one program at the same time with these. Instead of a console/logger, or in addition to, the Weatherlink Live can receive dta from ISS and upload to Weatherlink.com and also work with CumulusMX, and with the Weatherlink Live more than one program can have access to the WLL at the same time.

CumulusMX can run on PC or Pi, and has a built-in DB. CumulusMX can upload to all the usual weather services like WU, CWOP, WOW, etc., and your DB.
CumulusMX connected to Davis station and extra sensors can also receive and log additional sensors like those offered by Ecowitt/Ambient.

WIfiLogger is wifi to router, and can also be used as a stand-alone - i.e. upload directly to the many weather services like WU, CWOP, WOW, WC, Windy, PWSweather, AWEKAS, WL.com, and also upload realtime.txt and wflexp.json files, and MySQL.

Many options

Enjoy,
Paul

My solution to this issue is a Meteo-Pi connection which works very well. It just plugs into the back of the Davis console and connects to the HAT connector on the RPi. The setup instructions from Prodata are clear and the unit has worked faultlessly since installation a couple of years ago. The data stream is recognised by CMX and the bonus is that another source of WiFi error is removed.