Hello Is it possible to find out in xFilter or xBestIndex which columns were selected? That is, if I do "SELECT a, b, c FROM t" where t is a virtual table, I would like to know in xFilter or xBestIndex that the result will only consist of the rows a, b and c.
I know that xColumn will only get called for these columns. The reason why I would like to know before that, is that xFilter will do a "SELECT *" on another table and it needs read a bunch of its rows before the first xColumn can be called (I'm doing interpolation and need to look ahead). But in most cases its a huge waste of resources to read every column ahead of xColumn. I only need to read those columns that xColumn will be called on. I could potentionally save GB's of memory if I know what wont be needed in xFilter. -- Steinar _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
