For me, source_id = 2016-04-18 15:46:14 eba27d4d17a76884292667d570d542e580ee3e77 Windows 10 1511 Pro, i7-3632QM 2.4Ghz, 16 GB Ram, 1 TB 850 Pro SSD
with secure_delete=0 either drop table testuniqueuuid; or the sum of both delete from testuniqueuuid; drop table testuniqueuuid; takes under 2 seconds total real time, with secure_delete=1 either drop table testuniqueuuid; or the sum of both delete from testuniqueuuid; drop table testuniqueuuid; takes just over 10 seconds. In the cases with separate delete from and drop, the majority of time is spent in delete from (where it presumably overwrites and frees the rows and index) and the drop takes just milliseconds. With only the drop, the total time is more or less the same. If the delete from and drop are run in a single transaction, the total time for the transaction is closer to the time for just the drop of the populated tables, but only by a few milliseconds. Nothing seems out of sorts to me, at least with the database file. > -----Original Message----- > From: sqlite-users-bounces at mailinglists.sqlite.org [mailto:sqlite-users- > bounces at mailinglists.sqlite.org] On Behalf Of Cecil Westerhof > Sent: Wednesday, 20 April, 2016 17:55 > To: SQLite mailing list > Subject: Re: [sqlite] Is it possible that dropping a big table takes very > long > > 2016-04-20 22:40 GMT+02:00 Cecil Westerhof <cldwesterhof at gmail.com>: > > > 2016-04-20 22:35 GMT+02:00 Cecil Westerhof <cldwesterhof at gmail.com>: > > > >> 2016-04-20 22:21 GMT+02:00 Scott Robison <scott at casaderobison.com>: > >> > >>> On Wed, Apr 20, 2016 at 2:00 PM, Cecil Westerhof > <cldwesterhof at gmail.com > >>> > > >>> wrote: > >>> > >>> > How stupid that I did not think about Google Drive. :'-( Here it is: > >>> > https://drive.google.com/file/d/0BzW5q7uL-6z0SDdya2REaFNFUVE > >>> > > >>> > ?I am very curious. > >>> > > >>> > >>> I downloaded this and opened it with sqlite3.exe shell version 3.11.0. > >>> > >>> D:\>\bin\sqlite3.exe checkUUID.sqlite > >>> SQLite version 3.11.0 2016-02-15 17:29:24 > >>> Enter ".help" for usage hints. > >>> sqlite> .schema > >>> sqlite> > >>> > >>> It's a big enough file, but there is no schema present. > >>> > >> > >> ?That is strange, because I get: > >> sqlite3 checkUUID.sqlite > >> SQLite version 3.8.7.1 2014-10-29 13:59:56 > >> Enter ".help" for usage hints. > >> sqlite> .schema > >> CREATE TABLE testUniqueUUID ( > >> UUID blob, > >> > >> PRIMARY KEY(UUID) > >> CHECK(TYPEOF(UUID) = 'blob' AND > >> LENGTH(UUID) = 16 AND > >> SUBSTR(HEX(UUID), 13, 1) == '4' AND > >> SUBSTR(HEX(UUID), 17, 1) IN ('8', '9', 'A', 'B') > >> ) > >> ); > >> > >> > >> ?I am going to investigate.? > >> > > > > ?Interesting: when I unzip the .gz file, I have the same problem. > > Something went wrong. I will try to correct it.? > > > > ?This one I download, unpacked and tried. It worked. So it should be > correct now: > https://drive.google.com/file/d/0BzW5q7uL-6z0UjFhRWZWSENnZW8/ > > ?Made with zip. > > -- > Cecil Westerhof > _______________________________________________ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users