Hello - I have a question on SQLite query data buffering. I'm successfully using SQLite v3.22.0 on an embedded ARM processor from ST with SD card. The database file size is about 750MB. The file system is Segger emFile FAT32. I've configured SQLite to use 6MB RAM for heap. I've done some query time benchmarking and found that the very first R*Trees query takes about 1.6 seconds to complete. Each successive R*Trees query (same query string with slightly different search parameters) takes about 11ms to complete. Being new to SQLite and spatial queries, I'm trying to understand the substantial query time differences... does SQLite cache data from each query for future queries? The initial query:SELECT LINK_ID, FROM_REF_ELEVATION, TO_REF_ELEVATION FROM adas_link_geometry, idx_adas_link_geometry WHERE adas_link_geometry.ROWID = idx_adas_link_geometry.id AND minLat > 454760320 AND maxLat < 454800320 AND minLong > -1226807072 AND maxLong < -1226767072;
Thanks in advance,Dave _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
