Now we get down to the first real problem that of the ATTACH. I have never been able to get that to work. If I could have got the ATTACH to work I probably would never have had to ask the synchronisation question. Although I have never had to do it before in SQLite, I have worked a lot with SQL Server doing synchronisation there
On 13 August 2015 at 07:08, Simon Slavin <slavins at bigfraud.org> wrote: > > On 13 Aug 2015, at 5:55am, Chris Parsonson <z2668856 at gmail.com> wrote: > > > The tables are very simple. They have a primary key, but no relationship > > between tables in the sense that you mean. Synchronisation will be add > new > > rows, and update some rows, no deletions > > To access two different databases with one database connection, use the > ATTACH command. > > Method 1 > -------- > > To find rows which are in one table but not in the other, use EXCEPT > > SELECT primaryKeyColumn FROM databasea.myTable EXCEPT SELECT > primaryKeyColumn FROM myTable > > In cases where a row has been updated with a new value in one column, how > do you propose to decide which value is the 'right' one to put in both > databases ? > > Method 2 > -------- > > Ignore Method 1. In each copy of your database keep a log of all INSERT > and UPDATE commands executed since the last 'synchronize': > > CREATE TABLE commandsSinceLastSynch (theCommand TEXT) > > To synchronise the two copies, play back the log for copy A to copy B and > the log for copy B to copy A. > > Simon. > _______________________________________________ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > -- Chris Parsonson 083 777 9261
