Sairam Gaddam wrote: > I know that SQLite will perform some internal select statements when > executing a join query but will it break a join query and execute in parts > ???
SQLite executes all joins in parts, i.e., it is not possible to do more than one lookup of a joined field. (SQLite implements only nested loop joins.) However, SQLite tries to compute output rows dynamically, i.e., it takes the first row of the first table, looks up the matching row(s) in the second table and then in other joined tables, outputs the result row, and then continues with the second row. In other words, the temporary result of a join between all the rows in two tables is not actually stored as a whole anywhere (unless needed for sorting or grouping). Regards, Clemens
