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copied!<p>The best way to UPDATE many rows at once is :</p> <ul> <li>CREATE TEMP TABLE</li> <li>Fill it with (primary key, new values) with a big INSERT</li> <li>UPDATE table JOIN temptable USING (primary key) SET table.oldvalue=temptable.newvalue</li> </ul> <p>Update :</p> <pre><code>create table test ( id integer primary key, p point not null ); insert into test (id,p) select id, POINT( id%100, floor(id/100) ) from serie limit 10000; alter table test add spatial index spi (p); select id, AsText(p) from test; +----+-------------+ | id | AsText(p) | +----+-------------+ | 1 | POINT(1 0) | | 2 | POINT(2 0) | | 3 | POINT(3 0) | ... | 98 | POINT(98 0) | | 99 | POINT(99 0) | | 100 | POINT(0 1) | | 101 | POINT(1 1) | ... | 9999 | POINT(99 99) | | 10000 | POINT(0 100) | +-------+--------------+ EXPLAIN SELECT id,AsText(p) from test where Contains( GeomFromText('POLYGON((0 0,0 10,10 10,10 0,0 0))'), p ); +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ | 1 | SIMPLE | test | range | spi | spi | 34 | NULL | 112 | Using where | +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ create temporary table test2 ( id integer primary key, p point not null ); insert into test2 (id,p) select id, POINT( 1+(id%100), 1+floor(id/100) ) from serie limit 10000; update test, test2 set test.p=test2.p where test.id=test2.id; EXPLAIN SELECT id,AsText(p) from test where Contains( GeomFromText('POLYGON((0 0,0 10,10 10,10 0,0 0))'), p ); +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ | 1 | SIMPLE | test | range | spi | spi | 34 | NULL | 102 | Using where | +----+-------------+-------+-------+---------------+------+---------+------+------+-------------+ </code></pre> <p>No problem here (MySQL 5.1.41)</p>

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