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mysql建立索引删除索引很慢的解决
目前情况
建立索引非常慢,需8分钟...
目前环境:
----------------
table行： 30W
版本5.0.45-community-nt
系统XP CPU2.11G MEM2G
测试语句：
----------------------
CREATE INDEX i_atian ON gaopinzi(atian)DROP INDEX i_atian ON gaopinzi
解决方法:调整my.ini的参数配制..不个_size统统加大10倍..
----------------------------------------------------
原来
read_buffer_size=64Kread_rnd_buffer_size=256Ksort_buffer_size=203Kinnodb_additional_mem_pool_size=2Minnodb_log_buffer_size=1M[SQL] DROP INDEX i_atian ON gaopinzi
受影响的行: 322750
时间: 459.031s
my.ini 提升10倍数
read_buffer_size=80M
read_rnd_buffer_size=80M
sort_buffer_size=88M
innodb_additional_mem_pool_size=200M
innodb_log_buffer_size=100M
QL] DROP INDEX i_atian ON gaopinzi
受影响的行: 322750
时间: 33.766s
[SQL] CREATE INDEX i_atian ON gaopinzi(atian)
受影响的行: 322750
时间: 35.890s
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