mysql用load语句实现简单etl操作

LOAD DATA LOCAL INFILE 'D:\\baidu\\Desktop\\aaa.csv'INTO TABLE test.m CHARACTER SET GBKFIELDS TERMINATED BY ',' ENCLOSED BY ''LINES TERMINATED BY '\r\n' IGNORE 1 LINES(gender,id);

如果有主键列和唯一列，则会根据唯一性约束排除重复值。

添加唯一性约束：ALTER table test.m add UNIQUE key1(gender,count);

删除唯一性约束：ALTER table test.m drop index key1;

唯一性约束=索引，主键=非空索引=非空唯一约束