Repeatation issue

I have created one schema and one of my friend created another schema after that i want _id fields from her schema, so that i import her csv file in my dataset and use it …but in her schema she has created 140 _id and after import her schema as a dataset in my schema than her _id field are repeated in my schema _id , i want 138 _id from her data but it repeated the _id ever time…can you please give me solution for that?

Thank u