topic Re: Empty an autoincremental qvd in QlikView

Empty an autoincremental qvd

Diego_780 — Mon, 26 Sep 2022 07:42:30 GMT

Hello developers,

So I have this qvd that it gets automatically fed if someone acces to a QlikApp, by addin this entry with date and name lets say to the acces.qvd. I want to make a new qvd (historic.qvd), to have all the entrys that has acces.qvd (so store acces.qvd data into historic.qvd) but also I want to delete each time acces.qvd, so it can only have or new entrys, or blank I wanna reset acces.qvd each time I reload and store the acces.qvd data into historic.qvd.

I´ve seen some respones in the forums but I don´t know if they answer my question, I think you can´t reset a qvd in general, so I´ve seen a way to like, create a new blank table and upload it into the existing qvd? Any answer is appreciated thanks!

Re: Empty an autoincremental qvd

marcus_sommer — Tue, 27 Sep 2022 13:42:29 GMT

I'm not sure if I understand your doing right but a qvd couldn't be emptied. At least not directly but a qvd could be overwritten and must not mandatory contain any record. You may try something like this:

t: load * from t.qvd where 1 > 2; store t into t.qvd; drop tables t;

- Marcus

Re: Empty an autoincremental qvd

Diego_780 — Tue, 27 Sep 2022 14:11:18 GMT

Thanks for the response!

I finally solved it by loading inline the names of the columns only with no data:

EMPTY_TABLE: Load * Inline [ Column1, Column2, Column3 ]; Store EMPTY_TABLE into acces.qvd (qvd);

So with this, I get to "reset" the data from acces.qvd, but before that I have stored that info into another qvd.

Thanks!