mysql 多表联合查询

多表联合left join

select p.*,c.*,sc.*, se.*
from  ((p left join  c on p.channel=c.channel) left join sc on  p.channel=sc.channel) left join se on  p.channel=se.channel;

mysql导入数据

load data local infile '$WORK_HOME/date.dat' into table search fields terminated by '\t';