On Tue, 25 Dec 2007 19:24:48 +0100, "Mag. Wilhelm Braun" <[EMAIL PROTECTED]> wrote:
>Thanks as in my case just number 2 is possible a quite 'silly' question: >How do you normally check if Update was successful if the specified row >did not exists. > >e.g: UPDATE MyTable SET Account='MyAccountName' WHERE ID=50 > >If row 50 does not exists it does nothing and I seem not to get any return to >know? There is an SQLite function for that. http://www.sqlite.org/c3ref/total_changes.html >using pysqlite. I don't know the pysqlite wrapper, but this may be of help: http://www.initd.org/pub/software/pysqlite/doc/usage-guide.html Search for "total_changes attribute". >Thanks W.Braun > > > >A. Pagaltzis wrote: >> * Mag. Wilhelm Braun <[EMAIL PROTECTED]> [2007-12-25 15:10]: >> >>> QUESTION: is there a better way to make this important >>> decision? using Sqlite >>> >> >> 1. If you are changing the entire row on every update, you can >> simply use `INSERT OR REPLACE` (assuming there is a UNIQUE >> column) to always do this in a single query. >> >> See <http://sqlite.org/lang_conflict.html>. >> >> 2. If you only want to update some of the columns, particularly >> if you are likely to update rows several times, you can use >> `UPDATE` to try and update, and if this did not affect any >> rows you do an `INSERT`. >> >> In #1, you always get the job done with a single query. In #2, >> you are usually done after the first but sometimes need a second. >> Both are more efficient than your current approach, which always >> runs two queries. >> >> Regards, >> -- ( Kees Nuyt ) c[_] ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
