jiangbeilu 发表于 2016-8-25 16:47 
这个问题,你可以把factor类型的变量,用as.character转成字符,或者直接在开始读入该数据时,先运行option ...
> attach(new_pipeline_data)
The following objects are masked from mongo_pipeline_data (pos = 3):
CDE.AcceptableType, Difftime, RegistrationType, StatusCN, X_id
The following objects are masked from mongo_pipeline_data (pos = 4):
CDE.AcceptableType, RegistrationType, StatusCN, X_id
The following objects are masked from mongo_pipeline_data (pos = 6):
CDE.AcceptableType, RegistrationType, StatusCN, X_id
这是什么意思哦