Re: [sqlite] Loading a database from memory
On Wed, Jul 20, 2011 at 3:41 AM, st@gz wrote: > Implement sqlite-vfs with pure memory block. > > > spmemvfs-0.3.tar.gz > > > > http://code.google.com/p/sphivedb/downloads/list What is the license of spmemvfs? There is nothing stating it in the source code, but the website http://code.google.com/p/sphivedb/ seems to imply GPL v2, unless that is only referring to sphivedb. Thanks. > > > > -- Original -- > From: "Simon Slavin"; > Date: Tue, Jul 19, 2011 10:10 PM > To: "General Discussion of SQLite Database"; > > Subject: Re: [sqlite] Loading a database from memory > > > > On 19 Jul 2011, at 3:04pm, Pavel Ivanov wrote: > >>> So you can copy any block of memory you have a handle for into that, use >>> SQLite to manipulate the data while it's in memory >> >> Simon, could you elaborate what you meant by that. To my knowledge you >> can't just copy any block of memory into SQLite and make it treat this >> memory block as database. Did you meant something else? > > Apparently I misremembered. I thought you could use the sqlite3 handle and > find a pointer to the start of a block of memory the data was stored in. But > now I see no way to do this. Sorry about the misinformation. > > Simon. > ___ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > ___ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Loading a database from memory
On Tue, Jul 19, 2011 at 4:39 PM, Glenn McCord wrote: > On Tue, Jul 19, 2011 at 4:31 PM, Simon Slavin wrote: >> >> On 19 Jul 2011, at 5:17am, Glenn McCord wrote: >> >>> Hi. I've been trying to find out the best way of loading an sqlite >>> database from memory. Basically I'd like to be able to save a small >>> sqlite database as meta data to an audio file, i.e. an mpeg4 >>> container. I'd then be able read, modify then write it back to the >>> file. >> >> You can use the SQLite backup API to transfer an entire database from or to >> memory: >> >> http://www.sqlite.org/backup.html >> I've just had a quick look at the backup API, and it seems to make use of filenames and sqlite databases, which is not exactly what I'm after. What I need is the ability to read in an array of bytes, (read from meta data of an mpeg4, say, via fstream or some other equivalent), that represents the raw data of an sqlite database. I'm trying to avoid having to parse in that data, save it to a separate file first, then load it using a mysql open() call. I'll admit that I only had a quick read, so may have missed something. Thanks >> However, I'm not sure of the wisdom of saving data in this way. The SQLite >> file format is not simple or easy to inspect, and uses up a lot of space >> because it has to hold indexing information. Would it not make more sense >> to encode your data as XML or JSON and save this (or a .zipped version of >> this) in your MPEG4 instead ? >> > > I was thinking the same thing, but some of the guys around the office > are pretty keen on the idea of using sqlite. I'm just doing the > required research and weighing up the options. Using JSON seems like a > good idea. > > Thanks for the link. > >> Simon. >> ___ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >> > ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Loading a database from memory
On Tue, Jul 19, 2011 at 4:31 PM, Simon Slavin wrote: > > On 19 Jul 2011, at 5:17am, Glenn McCord wrote: > >> Hi. I've been trying to find out the best way of loading an sqlite >> database from memory. Basically I'd like to be able to save a small >> sqlite database as meta data to an audio file, i.e. an mpeg4 >> container. I'd then be able read, modify then write it back to the >> file. > > You can use the SQLite backup API to transfer an entire database from or to > memory: > > http://www.sqlite.org/backup.html > > However, I'm not sure of the wisdom of saving data in this way. The SQLite > file format is not simple or easy to inspect, and uses up a lot of space > because it has to hold indexing information. Would it not make more sense to > encode your data as XML or JSON and save this (or a .zipped version of this) > in your MPEG4 instead ? > I was thinking the same thing, but some of the guys around the office are pretty keen on the idea of using sqlite. I'm just doing the required research and weighing up the options. Using JSON seems like a good idea. Thanks for the link. > Simon. > ___ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Loading a database from memory
Hi. I've been trying to find out the best way of loading an sqlite database from memory. Basically I'd like to be able to save a small sqlite database as meta data to an audio file, i.e. an mpeg4 container. I'd then be able read, modify then write it back to the file. I'm starting to get the impression that the only way for me to do this is to make my own vfs layer... http://stackoverflow.com/questions/3839158/using-sqlite-with-stdiostream Would sqlite's test_onefile.c example code be the most appropriate starting point? http://www.sqlite.org/src/doc/trunk/src/test_onefile.c If someone could offer ways of achieving this, or could at least clarify that a vfs is the only way to go, then I'd appreciate the feedback. Thanks. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
