Re: [sqlite] Merging databases
Krzysztof wrote: > I have daemon on server which each day create new sqlite database. Client > application can download and present these databases. For example: User > want to see data from last week so client application download 7 > files. Advantage of this defragmentation is that it don't need to download > big files. Disadvantage is that create queries is tricky. So here is my > question. Is SQLite has some function for merging data? I'm wondering about > ATTACH DATABASE, but maybe there is a better way? You can indeed use attached databases to merge data: ATTACH DATABASE 'day42.sqlite' AS 'day42'; INSERT INTO MyTable SELECT * FROM day42.MyTable; If the data does not have a timestamp, you'd have to add it: INSERT INTO MyTable(name, value, whatever, day) SELECT name, value, whatever, 42 FROM day42.MyTable; Regards, Clemens ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Merging databases
Hi, I have daemon on server which each day create new sqlite database. Client application can download and present these databases. For example: User want to see data from last week so client application download 7 files. Advantage of this defragmentation is that it don't need to download big files. Disadvantage is that create queries is tricky. So here is my question. Is SQLite has some function for merging data? I'm wondering about ATTACH DATABASE, but maybe there is a better way? Regards ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Merging databases
Hello, Imagine you have a simple database with two tables, and a third to join them as a many-to-many relationship. Someone sends me an SQLite database as a file which has the same structure, but the data is different. I want to merge these two databases together keeping all of the relationships intact, without duplicating data. For example, if the tables were "customers" and "products" and the one in between "orders", there is the possibility that some customers and/or products might be the same, but with different primary keys. The problem is that since the databases were independently created, a simple union will break the relationships since the primary keys will overlap. I can think of brute force ways to do this, but I was wondering if anyone might have a good algorithm or technique to accomplish this efficiently. Cheers! Demitri
