Good advice Peter .. I will give this a try. Craig
On Wednesday, July 31, 2024 at 11:18:26 AM UTC+12 p q wrote: > if I were doing it, I would use SQLite to execute the queries and then I > would check my work with DB Browser. > > I think you may have misunderstood my backup comment. I would practice on > a copy of my database. Once I had the queries correct, then I'd stop Weewx, > make another backup of the database to be safe, perform the operation, and > then restart Weewx. If you're sure you won't mess up, you can skip practice > and the extra backup. > > On Tue, Jul 30, 2024 at 4:09 PM Craig Young <[email protected]> wrote: > >> Absolutely, I would backup the database first .. your idea of using a two >> pass method would work .. would I do that with the weewx database utility >> or some linux based sql app like DB Browser for SQLite? >> >> On Wednesday, July 31, 2024 at 10:45:47 AM UTC+12 p q wrote: >> >>> Do yourself a favor and make a backup copy. Test out whatever method you >>> chose on the copy. >>> >>> As to the query, I think you could fill the Signal field with 0.0 and >>> then do an UPDATE SQL query where outTemp > 10.0. You can find the SQL >>> syntax online. >>> >>> On Tue, Jul 30, 2024 at 3:30 PM Craig Young <[email protected]> >>> wrote: >>> >>>> WeeWx version: 4.10.2 >>>> DB: SQLite3 >>>> >>>> What is the best method for recalculating an item in the entire >>>> database? Specifically, I want to do this: >>>> >>>> signal4 = 1.0 if outTemp < 10.0 else 0.0 >>>> >>>> So I want the DB update method to look at each record and if the >>>> temperature (in that record) is less than 10.0 C then set the signal4 >>>> value >>>> in that record to 1.0, otherwise, set the signal4 value to 0.0. >>>> >>>> Do I use wee_database --calc missing? >>>> or some other method? >>>> >>>> There are currently 575,000 records in the database so I really don't >>>> want to mess this up. I assume I need to stop WeeWx while doing this? >>>> >>>> Craig >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "weewx-user" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/weewx-user/df5146de-9a51-4c05-888a-17a663d774f4n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/weewx-user/df5146de-9a51-4c05-888a-17a663d774f4n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> >>> >>> -- >>> Peter Quinn >>> (415)794-2264 <(415)%20794-2264> >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "weewx-user" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/weewx-user/119eea81-a564-4b8c-b84f-3b9bb857e6d6n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/weewx-user/119eea81-a564-4b8c-b84f-3b9bb857e6d6n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > Peter Quinn > (415)794-2264 <(415)%20794-2264> > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/6337b7ea-6907-4807-9628-df74b0899a23n%40googlegroups.com.
