Hello, I am trying to create a simple virtual table that acts as wrapper for a normal database table for a specific query. For example, consider that I have tables A and B in my database and the query: select count(A.id) from A CROSS JOIN B where A.id=B.id
Now I am using a virtual table acting as wrapper for table B, so I can execute the query select count(A.id) from A CROSS JOIN w where A.id=w.id, where w is the virtual table instance, and get the same result. My problem is that the second query is about 2 times slower. I would normally expect some overhead, but this seems quite slow, so I was wondering if there is something wrong with my code. I am using a prepared statement in connect method for query "select id from B where id=?1" and reset/bind/step in filter method and (if there are more results) step in next method. Here's my code (I am just setting id=0 to denote eof) http://pastebin.com/ce8b4aLL Do you think there's something wrong or it's an unavoidable overhead that comes with the virtual table usage? Are there any chances to improve performance? thanks, Dimitris _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
