> 1. Does BLOB type field cause any performance issues compared to using TEXT> > when doing inserts/updates. In other words, if they use the same number of> > bytes, would there be any difference in performance? I believe it's a little weird choice as TEXT fields have some additional features that you don't want to have with binary data. But to answer your question I think performance would depend on encoding in your database (UTF-8 vs UTF-16) and the functions you use to bind TEXT value.
> 2. When you store multiple tables, does each table get stored on a page by > itself, so the larger the page size, the more likely you would see > contiguous items for a table? Yes, every table has its own set of pages, their data doesn't mix into same pages. > 3. How does the sqlite page size correlate with the file system block size? > In other words, if sqlite uses a page size of 1K and the file system uses a > block size of 4K, would you still end up writing 4K even if you changed only > 1K? Yes, at the OS level (i.e. SQLite doesn't do anything for that to happen) you'll end up reading 4K (if it's not already in cache) and writing 4K back with 1K of them changed. Pavel On Thu, Sep 15, 2011 at 10:04 PM, Andy Stec <andys...@gmail.com> wrote: > We are trying to determine how BLOB type and page size impact performance. > I have a few questions related to that: > > 1. Does BLOB type field cause any performance issues compared to using TEXT > when doing inserts/updates. In other words, if they use the same number of > bytes, would there be any difference in performance? > > 2. When you store multiple tables, does each table get stored on a page by > itself, so the larger the page size, the more likely you would see > contiguous items for a table? > > 3. How does the sqlite page size correlate with the file system block size? > In other words, if sqlite uses a page size of 1K and the file system uses a > block size of 4K, would you still end up writing 4K even if you changed only > 1K? > _______________________________________________ > 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
