On Thu, Sep 19, 2019 at 10:20 AM Rowan Worth <row...@dug.com> wrote: > On Thu, 19 Sep 2019 at 16:03, Dominique Devienne <ddevie...@gmail.com> > > On Wed, Sep 18, 2019 at 6:43 PM Clemens Ladisch <clem...@ladisch.de> > > > Peng Yu wrote: > > > > Is there a better way to just return an exit status of 0 for > > > > a sqlite3 DB file and 1 otherwise? > > > > dd bs=16 count=1 < some.db > sqlite3-signature > > > cmp --bytes=16 sqlite3-signature /tmp/tmp.erZ5aS6PUX.sqa > /dev/null > > > [ $? = 0 ] && echo SQLite DB > > > > > > I'm actually surprised sqlite3[.exe] itself doesn't have a more to do > that. > > As usual, sqlite doesn't touch the DB file until it is asked to. Try > "sqlite3 FILENAME 'pragma schema_version'" on some random file and you'll > get "Error: file is encrypted or is not a database". But note that trying > the same on a non-existent file will succeed, and additionally create an > empty file. >
Thanks. Good tip. Need double not single quotes on Windows. And error code of 26 if a bit weird, but this works well otherwise: D:\>sqlite3 TypedEntity.h 'pragma schema_version' Error: unrecognized token: "'pragma" D:\>sqlite3 TypedEntity.h "pragma schema_version" Error: file is not a database D:\>echo %ERRORLEVEL% 26 D:\>sqlite3 SOME.db "pragma schema_version" 58 D:\>echo %ERRORLEVEL% 0 > > You'd think sqlite3[.exe] is the best suited to figure out if a file is a > > valie SQLite database or not, > > It still is: sqlite3 FILENAME 'pragma integrity_check' > > Parsing the header doesn't tell you whether the DB is valid, but if that's > all you want to do I suggest the ubiquitous file(1) command which reports > "SQLite 3.x database" for a [non-empty] sqlite db file. > I'm well aware of that. We were discussing an alternative to the *nix file command, and integrity_check goes way beyond (and is way slower) than checkinga file type. You might as well through FK checks with foreign_key_check if you are going there :). pragma quick_check would be more appropriate, if one wants to go the extra mile, w/o slowing things down too much. But again, thanks for this tip. Good one. --DD _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
