So just to clarify (hello?), the index which *should* be used (EXPLAIN says so) and *should* make the query run faster than 4 seconds either isn't used (why?) or simply doesn't speed up the query (again, why?).
+----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ | 1 | SIMPLE | qs | range | coord | coord | 27 | NULL | 5260 | Using where | +----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ SELECT id, province, latitude, longitude, AsText(coordinates), s_ts_r_m, quartersection FROM qs WHERE MBRContains(GeomFromText('POLYGON((51.62582589 -114.82248918,51.65126254 -114.82248918,51.65126254 -114.78150333,51.62582589 -114.78150333,51.62582589 -114.82248918))'), coordinates) 8 rows in set (3.87 sec) On 2009-12-27, at 3:59 PM, René Fournier wrote: > So... there is an index, and it's supposedly used: > > mysql> EXPLAIN SELECT id, province, latitude, longitude, AsText(coordinates), > s_ts_r_m, quartersection FROM qs WHERE > MBRContains(GeomFromText('POLYGON((51.62582589 -114.82248918,51.65126254 > -114.82248918,51.65126254 -114.78150333,51.62582589 -114.78150333,51.62582589 > -114.82248918))'), coordinates); > +----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ > | id | select_type | table | type | possible_keys | key | key_len | ref | > rows | Extra | > +----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ > | 1 | SIMPLE | qs | range | coord | coord | 27 | NULL | > 5260 | Using where | > +----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+ > 1 row in set (0.00 sec) > > But when I run the query: > > mysql> SELECT id, province, latitude, longitude, AsText(coordinates), > s_ts_r_m, quartersection FROM qs WHERE > MBRContains(GeomFromText('POLYGON((51.62582589 -114.82248918,51.65126254 > -114.82248918,51.65126254 -114.78150333,51.62582589 -114.78150333,51.62582589 > -114.82248918))'), coordinates) > -> ; > +--------+----------+-------------+---------------+----------------------------------+--------------+----------------+ > | id | province | latitude | longitude | AsText(coordinates) > | s_ts_r_m | quartersection | > +--------+----------+-------------+---------------+----------------------------------+--------------+----------------+ > | 444543 | AB | 51.63495228 | -114.79282412 | POINT(51.63495228 > -114.79282412) | 04-031-06 W5 | N4 | > | 444564 | AB | 51.64941120 | -114.79283278 | POINT(51.6494112 > -114.79283278) | 09-031-06 W5 | N4 | > | 444548 | AB | 51.63497789 | -114.81645649 | POINT(51.63497789 > -114.81645649) | 05-031-06 W5 | N4 | > | 444561 | AB | 51.64943119 | -114.81643801 | POINT(51.64943119 > -114.81643801) | 08-031-06 W5 | N4 | > | 444547 | AB | 51.62775680 | -114.80475858 | POINT(51.6277568 > -114.80475858) | 05-031-06 W5 | E4 | > | 444549 | AB | 51.63498028 | -114.80479925 | POINT(51.63498028 > -114.80479925) | 05-031-06 W5 | NE | > | 444560 | AB | 51.64220442 | -114.80478262 | POINT(51.64220442 > -114.80478262) | 08-031-06 W5 | E4 | > | 444562 | AB | 51.64942854 | -114.80476596 | POINT(51.64942854 > -114.80476596) | 08-031-06 W5 | NE | > +--------+----------+-------------+---------------+----------------------------------+--------------+----------------+ > 8 rows in set (3.87 sec) > > So, there are ~2.6 million rows in the table, and coordinates is > spatially-indexed. Yet the query requires nearly 4 seconds. What am I doing > wrong? > > ...REne -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org