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HomeDatabaseMysql Tutorial十六、mysql 分区之 简单sql优化2_MySQL

1.索引的分类    B-Tree 基本支持    HASH 只有memory支持    R-Tree myisam支持    Full-text myisam支持(全文索引)2.Memory引擎下只有“=”条件才会使用索引===============================  导入数据的优化  ========================3.如何提高myisam的导入效率  alter table emp disable keys;关闭索引  load data infile 'aa.sql' into table emp;导入数据到emp  alter table emp enable keys;开启索引 4.如何提高innodb的导入效率  导入的数据按照主键的顺序排列即可5.导入数据前关闭唯一性检查  set unique_checks = 0 ;  load data infile ....  set unique_checks = 1 ; 开启检查===============================  Insert 的优化  ========================1.使用多值插入 insert into emp values (1,2,3),(1,2,3),.....===============================  分页 的优化  ==========================1.使用inner join内联2.应用程序端做处理,大概思路就是记录上一页的最后一条记录的id是多少,下一页就以这个id为起始值  但这个必须保证id为唯一性

 

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