Please sorry for my terrible Engilsh. :) Thanks for the answer.
Yes, I know that it is bad design in the common case. But I have to use it because I have data which has following format: time | value_1 | value_2 | value_XXXX --------|-----------|-------------|---------------- [time_1] [value_1.1] [value_2.1] ... [value_XXXX.1] [time_2] [value_1.2] [value_2.2] ... [value_XXXX.2] [time_3] [value_1.3] [value_2.3] ... [value_XXXX.3] ................................................... And I must filter it by comparing some values, for example, as this: SELECT FROM table_name WHERE time > 1000 AND time < 1500 AND value_1 > value_2 + 3 OR value_456 != value_654 I asked this question because SQLite may use such algorithms which are very slow with very big number of colums and may be in this case it will work rapidly if, for example, I will combine values in such manner: time | value_1_to_value_100 | value_101_to_value_200 | ... --------|-------------------------|----------------------------|---- [time_1] [value_1_to_value_100.1] [value_101_to_value_200.1] ... [time_2] [value_1_to_value_100.2] [value_101_to_value_200.2] ... [time_3] [value_1_to_value_100.3] [value_101_to_value_200.3] ... .................................................................... And I will write some functions for extracting values from them and will filter data by following query: SELECT FROM table_name WHERE time > 1000 AND time < 1500 AND get_value(value_1_to_value_100, 1) > get_value(value_1_to_value_100, 2) + 3 OR get_value(value_400_to_value_500, 56) != get_value(value_600_to_value_700, 54) _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
